Grammarly (AI) vs Microsoft Copilot: Which AI Tool Should You Choose?

QA v1.0 — 2026-05-24 KST. content_status = qa_passed. Generated from templates/comparison-page-template.md and promoted after an independent Section B walk-through of qa/adsense-seo-quality-gate.md. Meta description (≤ 155 chars): Grammarly (AI) is an in-place writing assistant across the apps you already type in; Microsoft Copilot is Microsoft's multi-SKU 365 AI — here is the choice.

Quick recommendation

• Choose Grammarly (AI) if: the higher-value job is real-time grammar, clarity, tone, and light generative drafting across every app a knowledge worker already types in — Gmail, Outlook, Google Docs, Word, Slack, LinkedIn, Salesforce notes, browser form fields, mobile keyboards — and you want a single in-place writing layer that follows the writer between apps rather than living inside one productivity suite. Pricing is per writer (Free at $0/month with 100 generative-AI prompts per month, Pro at $12/month with 2,000 generative-AI prompts per member per month, Enterprise on Contact Sales with unlimited generative-AI prompts), and the buying motion is straightforward at the seat level.
• Choose Microsoft Copilot if: your organization already runs on Microsoft 365 (Word, Excel, Outlook, PowerPoint, Teams) and Windows, and you want the AI to appear as a native surface inside those apps — with admin tooling (Copilot Analytics, SharePoint Advanced Management, sensitivity labels), Microsoft Graph connectors (100+), Entra identity, and the rest of the Microsoft procurement story already in place. Accept that "Copilot" is an umbrella brand spanning multiple SKUs (consumer Copilot, Copilot Pro, Microsoft 365 Copilot Chat, Microsoft 365 Copilot Business, plus adjacent Copilots like GitHub Copilot, Microsoft Security Copilot, Microsoft Copilot Studio, Copilot in Azure, and Copilot in Power Apps sold separately) and that the per-user price depends on which SKU you actually intend to buy.
• Consider another option if: your daily work is reasoning-heavy reading and writing across long documents and you want a careful general-purpose chat assistant (Claude), your team's canonical documents live in Google Workspace (Gemini is the analogous in-suite AI for that case), your team's docs already live in Notion (Notion AI is the in-workspace AI for that case), your job is templated brand-voiced marketing content at volume (Jasper is the marketing-content workflow rather than a writing helper or a productivity-suite AI), or your job is shipping code every day on GitHub (GitHub Copilot is the right SKU and is sold separately from Microsoft Copilot even though both are Microsoft brands).
• Last verified: 2026-05-24 KST. Underlying source reads: grammarly.com/ai on 2026-05-21 KST (official AI feature URL only); grammarly.com/plans on 2026-05-22 KST (USD per-tier pricing and per-tier generative-AI prompt quotas visible); microsoft.com/en-us/microsoft-365/copilot/business on 2026-05-23 KST (USD per-user pricing visible); microsoft.com/en-us/microsoft-copilot on 2026-05-23 KST (free consumer surface and multi-SKU brand list visible; consumer Copilot Pro USD pricing was not visible on this fetch and is routed to "verify on official site").

Short answer

Grammarly (AI) and Microsoft Copilot are both regularly tagged as "AI for writing", but they live in different shaped surfaces and answer different procurement questions. Grammarly (AI) is Grammarly Inc.'s writing assistant — originally a grammar and clarity layer, now extended with generative drafting and rewriting — that lives as a browser extension, in-app integrations (Gmail, Google Docs, Word, Slack, Salesforce, LinkedIn), native desktop apps for Windows and macOS, and mobile keyboards. Its distinctive product idea is being the one writing surface that follows a single writer between every app they already type in. Microsoft Copilot is Microsoft's umbrella brand for AI assistants across its product surfaces, and the distinctive product idea across every SKU is the same shape: an AI surface that appears inside the productivity apps you already use, backed by the rest of Microsoft's ecosystem (Windows, Edge, Microsoft 365, Entra identity, Microsoft Graph).

That difference is most of the decision. If the job is making everyday writing across many apps cleaner, friendlier, and on-tone — replies, comments, internal updates, customer messages, LinkedIn posts, sales follow-ups, support drafts, and the steady stream of "make this shorter / clearer / friendlier" requests that fills a knowledge worker's day — Grammarly (AI) is the natural shape of product, and Microsoft Copilot is not really competing for that job (Microsoft Copilot does not appear inside Gmail, Google Docs, Slack, or Salesforce). If the job is drafting in Word, summarizing email in Outlook, building formulas in Excel, generating slides in PowerPoint, or recapping a Teams meeting — and your organization already pays for Microsoft 365 — Microsoft 365 Copilot Business's "AI does not require leaving the surface" pitch is the real one, and Grammarly's in-place writing layer is a complementary rather than a substitute purchase (Grammarly's strength inside Word and Outlook is a thin per-keystroke writing helper, not a draft-the-whole-doc / build-the-formula / recap-the-meeting in-app assistant).

For most knowledge-work organizations the honest framing is that the two products overlap only at the surface — both are "AI for writing" — and that the deeper job each is sized for is different. Grammarly (AI) is a per-writer subscription that pays for itself when the writer types meaningful prose across many apps every day. Microsoft 365 Copilot Business is a per-user subscription that pays for itself when the user actually does drafting / reading / summarizing / formula-building inside the Microsoft 365 apps every day, and that price assumes a separate qualifying Microsoft 365 license is already in place. An organization with both kinds of work — a heavy email and cross-app communication footprint, and heavy in-Word/in-Outlook/in-Excel productivity work — will likely buy both, sized to the populations that use each surface.

A pricing caveat applies on both sides. Grammarly's plan structure was read from grammarly.com/plans on 2026-05-22 KST: Free at $0/month with 100 generative-AI prompts per month and core grammar and tone features, Pro at $12/month with 2,000 generative-AI prompts per member per month and tone and rewrite suggestions, and Enterprise on Contact Sales with unlimited generative-AI prompts and admin and security controls. Microsoft 365 Copilot Business USD pricing was visible on microsoft.com/en-us/microsoft-365/copilot/business on 2026-05-23 KST at $18/user/month with annual commitment paid yearly, $18.90/user/month with annual commitment paid monthly, or $25.20/user/month on a monthly commitment, each requiring a separate qualifying Microsoft 365 license. The free consumer Microsoft Copilot at copilot.microsoft.com and Microsoft 365 Copilot Chat (included at no additional cost for users with eligible Microsoft 365 subscriptions) were also confirmed in the same fetch pass. Consumer Microsoft Copilot Pro USD pricing was not visible during the 2026-05-23 fetch — multiple Copilot Pro URL variants returned 403, 404, or timeout — and is therefore routed to the official Microsoft site rather than asserted on this page. Grammarly's Enterprise per-seat USD figure, regional pricing variants, and student/education discounts were not in scope of the 2026-05-22 fetch and are likewise routed to "verify on official site". Both vendors have moved SKUs, features, and quotas between releases; reconfirm before any pricing-sensitive commitment.

Comparison table

Use-case based choice

For writing and editing

This is the headline overlap between the two products and the most useful place to be specific, because both vendors lean on "AI writing" as a top-line benefit — but the writing surfaces are completely different.

Grammarly (AI) is the right fit when the writing surface is "wherever the writer happens to be typing today". Replies in Gmail, drafts in Outlook, comments in Google Docs, threads in Slack, posts on LinkedIn, customer messages in Salesforce notes, captions in a browser form, taps on a mobile keyboard — the consistent strength is real-time grammar and clarity assistance, one-click tone and rewrite suggestions, and in-place generative drafting, all without forcing the writer to switch into a separate chat tab. The Free tier at $0/month with 100 generative-AI prompts per month is a real evaluation surface for an individual writer; Pro at $12/month lifts the quota to 2,000 generative-AI prompts per member per month and adds tone and rewrite suggestions; Enterprise on Contact Sales is the per-seat sales motion for teams that need unlimited generative-AI prompts and admin and security controls. Microsoft Copilot does not appear inside Gmail, Google Docs, Slack, or Salesforce, so Grammarly is the natural shape of product when the team's writing is spread across apps that are not all in Microsoft 365.

**Microsoft Copilot is the right fit when the writing surface is Word, Outlook, or another Microsoft 365 app, and the job is more than "tighten this sentence".** Microsoft 365 Copilot Business explicitly lists drafting in Word, summarizing in Outlook, generating slides in PowerPoint, building formulas and analyzing data in Excel, and recapping meetings in Teams as in-app capabilities, plus AI-generated images, posters, banners, and videos and Copilot Notebooks for grouping work artifacts. The free consumer Copilot at copilot.microsoft.com and the free Microsoft Copilot app give a no-cost on-ramp for individual writers in the consumer surface; the Microsoft 365 Copilot Chat included with eligible M365 subscriptions adds the in-365 chat surface without an additional per-user fee; the paid Microsoft 365 Copilot Business SKU at $18/$18.90/$25.20 per user/month (depending on commitment) is where the full in-365-app surface is actually entitled, on top of a separate qualifying Microsoft 365 license. Grammarly's strength inside Word and Outlook is a per-keystroke writing helper — it does not draft a whole document from a brief, generate a deck from a notes page, or recap a meeting recording — and trying to compare Grammarly Pro at $12/month to Microsoft 365 Copilot Business at $18–$25.20/user/month as if they buy the same thing flattens the actual decision.

Both can co-exist on the same writer's seat without duplicating the same job. Many large organizations end up paying for both: Microsoft 365 Copilot Business to do the in-Word / in-Outlook / in-PowerPoint productivity work, Grammarly Pro or Enterprise to be the consistent grammar / clarity / tone layer that follows the same writer into Gmail (still common alongside Outlook), Slack, Salesforce notes, and LinkedIn drafts. The cost stack adds rather than substitutes; whether the second product earns its line item depends on how much serious writing each writer actually does outside the Microsoft 365 surface where Copilot is entitled.

For long, analytical, structured writing — 5,000-word memos, analyst notes, research summaries that demand careful reasoning across many inputs — neither tool is the natural pick. Grammarly's generative surface is sized for short-to-medium chunks in place (an email, a Slack message, a paragraph in a doc), not for sustained long-form reasoning; Microsoft Copilot inside Word can draft and rewrite, but the long-context analytical job is closer to what a dedicated chat assistant like Claude is positioned for. The practical pattern is to use a chat assistant for the heavy draft and bring the result back into the writer's normal surface (Grammarly to polish the prose, Word + Copilot to publish, send, and review).

For branded marketing copy at production volume — ads, landing pages, blog posts produced on a cadence, email sequences, social posts to feed a content calendar — neither tool is a marketing-content workflow. Grammarly can keep the prose clean and on-tone; Microsoft Copilot can polish copy inside Word and Outlook; but neither encodes per-channel templates, brand-voice memory, or marketing-campaign review structure. A dedicated marketing platform like Jasper is closer to that job.

The honest split for writing-heavy teams:

• If most of your team's serious writing is short-to-medium prose spread across many apps (email, chat, comments, CRM notes, social posts), default to Grammarly (AI). Free is enough to evaluate; Pro at $12/month covers the quota for most individual writers; Enterprise covers admin controls and unlimited generative-AI prompts.
• If most of your team's serious writing happens inside Word documents, Outlook drafts, or PowerPoint decks, default to Microsoft 365 Copilot Business at $18–$25.20/user/month depending on commitment, on top of a separate qualifying Microsoft 365 license.
• For teams that genuinely do both — and many knowledge teams do — paying for both products is common and not duplicative. They cover different surfaces and the work each does is different shape.
• Treat AI-drafted content as a proposal that needs human review, especially for legal, medical, financial, or HR-sensitive content. Neither tool's draft is a finished deliverable, and Grammarly's heuristic grammar suggestions can flatten a writer's voice if accepted blindly.

For coding and technical work

Neither product is the canonical "AI in the IDE" answer between these two. That answer is GitHub Copilot, which is a separate Microsoft brand sold separately from Microsoft Copilot — covered on its own page and in the Claude vs GitHub Copilot, Cursor vs GitHub Copilot, and GitHub Copilot vs Grammarly (AI) comparisons. The Grammarly (AI) vs Microsoft Copilot coding-and-technical comparison is therefore a narrow one.

Grammarly (AI) is not a coding assistant. It does not put completions into your editor as you type, it does not chat about a file open in VS Code, and it does not wrap a repo or a PR. Its strength is writing assistance across general communication and prose: cleaner commit-message prose, friendlier release notes, clearer Slack updates to non-engineering stakeholders, more polished design-doc drafts in Google Docs or Word — all surrounding-the-code surfaces rather than the code itself. For autocomplete, in-editor chat, or agent-style coding, see GitHub Copilot or Cursor.

Microsoft Copilot is not, in the consumer or Microsoft 365 SKUs, an in-IDE coding assistant either. The Microsoft 365 Copilot Business SKU lists custom agents with advanced reasoning, AI-powered search across work data, and Copilot Notebooks — useful around a developer's workflow (search a Microsoft 365 tenant for prior design docs, group meeting notes and decisions into a Notebook, ask grounded questions across work data), but none of that is the same product as completions and chat inside VS Code or JetBrains. For the in-IDE coding assistant on the Microsoft side, the answer is the separate GitHub Copilot product (Free at $0 with 50 agent/chat requests and 2,000 completions per month, Pro at $10/user/month, Pro+ at $39/user/month per the 2026-05-22 github.com/features/copilot/plans read covered on the GitHub Copilot tool page).

The honest split for developers:

• If your single most important workflow is in-editor completions and chat on GitHub-hosted repos, neither Grammarly nor consumer / Microsoft 365 Microsoft Copilot is your answer — GitHub Copilot is. Microsoft Copilot is not the same product as GitHub Copilot even though both are Microsoft brands; they are licensed and entitled separately.
• If your team writes a lot of prose around code — release notes, design docs, RFCs, internal updates, PR descriptions, customer-facing changelogs — Grammarly can be a useful prose-quality layer on top of the in-IDE coding assistant your team already pays for. It is not a substitute for the IDE assistant.
• If your organization's design docs, RFCs, runbooks, meeting recaps, and onboarding materials live in Microsoft 365 (Word, SharePoint, Outlook, Teams), Microsoft 365 Copilot Business's Microsoft Graph search and Copilot Notebooks can play an internal-research role around engineering's day-to-day work — also not a substitute for an in-IDE assistant.

None of this is a benchmark claim. Coding quality varies across languages, tasks, model versions, and prompt shapes, and both products' underlying model lineups change frequently. Treat any "X is better at code than Y" headline as out-of-date by the time you read it; do your own evaluation on the work you actually ship.

For research and fact-checking

Neither product is a citation-first answer engine; both produce confident text that needs to be checked against a primary source before it ships in a document. They fail differently because they draw on different content.

Grammarly (AI) does not pitch itself as a research tool at all. Its generative surface is drafting and rewriting short-to-medium prose, not citation lookup or multi-source synthesis. There is no internal-tenant search, no document grounding across a corpus, no inline citations. Treat any factual claim it generates the same way you would treat a draft you wrote yourself: verify against a primary source before it ships. The right use of Grammarly in a research-heavy workflow is editing — polishing prose that a human researcher (or a separate research assistant) has already produced.

Microsoft Copilot's research-style strength, in the paid Microsoft 365 Copilot Business SKU, is grounded chat across your organization's work data via Microsoft Graph (100+ connectors). That is a genuinely distinctive offer when the organization already has a sprawl of documents, emails, intranet content, and other knowledge inside Microsoft 365 and SharePoint. The free consumer Copilot at copilot.microsoft.com is closer to a general-purpose chat assistant with web grounding — useful for ad-hoc lookups but not the same internal-search-across-tenant story as the paid Business SKU. For organizations with serious internal research needs that span email, SharePoint, OneDrive, and Teams content, Microsoft Graph connectors are the differentiator.

For research specifically:

• For editing and polishing the writing that the research produces, Grammarly (AI) is the directly marketed answer between these two. It is not a research tool itself.
• For internal-document search and grounded chat across a Microsoft 365 tenant, Microsoft 365 Copilot Business with Microsoft Graph connectors is the directly marketed answer.
• For long-document reading and analytical reasoning across PDFs, contracts, or research papers you already have in hand, a dedicated chat assistant like Claude is closer to that job than either of these two.
• For citation-first web research with inline citations from many sources, a dedicated AI answer engine is closer to that job than either of these two.

Either tool's generated claims need to be verified against a primary source before they ship in a document or a code comment. Treat AI-generated summaries and answers as proposals, not as finished work.

For teams or businesses

The team buying decision is the bulk of the practical choice between these two products, and it splits cleanly because the two answer different procurement questions and are pitched to different buyers inside an organization.

Grammarly (AI) for teams is the product's natural buying surface. The 2026-05-22 page-body read of grammarly.com/plans showed Free at $0/month with 100 generative-AI prompts per month, Pro at $12/month with 2,000 generative-AI prompts per member per month, and Enterprise on Contact Sales with unlimited generative-AI prompts and admin and security controls. Enterprise is where seat management, brand voice / style-guide enforcement, SSO, and data-handling commitments typically live. The buyer is usually the team or department whose writers feel the friction every day — communications, sales, customer support, marketing operations — not centralized IT. The per-seat math is straightforward: $12/month per writer for Pro, sized to the population that types prose across multiple apps every day, with Enterprise added when the per-tier generative-AI prompt cap, admin controls, or SSO requirement becomes binding.

Microsoft Copilot for teams is structurally more complicated, because the same brand spans multiple SKUs with different entitlements and prices. Microsoft 365 Copilot Business is the headline per-user paid SKU at $18/user/month with annual commitment paid yearly, $18.90/user/month with annual commitment paid monthly, or $25.20/user/month on a monthly commitment, as read directly from microsoft.com/en-us/microsoft-365/copilot/business on 2026-05-23 KST. Crucially, that price is the add-on on top of a separate qualifying Microsoft 365 license; the headline number is not the total cost of running Copilot for an organization. Microsoft 365 Copilot Chat is included at no additional cost for users with eligible Microsoft 365 subscriptions and is the right surface to look at for a lower-feature on-ramp before scaling to Business. Microsoft 365 Copilot Enterprise pricing and education SKU pricing were not in scope of the 2026-05-23 fetch and should be confirmed through Microsoft's enterprise procurement channels and your account team. Consumer Microsoft Copilot Pro pricing was not visible on the same date (multiple Copilot Pro URL variants returned 403/404/timeout) and should be verified directly on Microsoft's official Copilot Pro page. The buyer is usually IT / workplace productivity, not a single writing-heavy department.

The choice is not "which is cheaper per seat" — those numbers are not directly comparable. Grammarly Pro at $12/month and Microsoft 365 Copilot Business at $18–$25.20/user/month look like spreadsheet-comparable lines, but they are buying different things. Grammarly Pro buys an in-place writing layer that follows a single writer across many apps with an explicit per-tier generative-AI prompt cap. Microsoft 365 Copilot Business buys the AI surface inside Word, Excel, Outlook, PowerPoint, and Teams plus admin tooling (Copilot Analytics, SharePoint Advanced Management, sensitivity labels, Entra identity) plus AI search across work data via Microsoft Graph (100+ connectors) plus AI-generated images / posters / banners / videos and Copilot Notebooks — and requires you to already be paying for a qualifying Microsoft 365 license per seat. The like-for-like comparison is not "AI for writing for $12 vs $18" but "in-place writing assistant across many apps vs in-Microsoft-365 productivity AI suite," and the answer depends on which of those two jobs the team actually does.

For an organization whose writers spread their daily writing across Gmail, Outlook, Slack, LinkedIn, Salesforce, and browser forms — a sales team, a customer-support team, a marketing-ops team, a recruiting team — Grammarly is the natural per-writer buy and Microsoft Copilot's in-365 advantage is mostly not exercised. For an organization whose daily work happens overwhelmingly inside Word, Outlook, Excel, PowerPoint, and Teams — most large knowledge-work enterprises standardized on Microsoft 365 — Microsoft 365 Copilot Business is the natural per-user buy and Grammarly is an optional complementary purchase for the populations whose writing also lands in non-Microsoft apps. For mixed organizations, paying for both, sized to the populations that use each surface, is common.

Several adjacent Copilots — GitHub Copilot, Microsoft Security Copilot, Microsoft Copilot Studio, Copilot in Azure, Copilot in Power Apps — are sold and entitled separately and are not covered by a Microsoft Copilot license. If your team needs AI in the IDE, GitHub Copilot is the right SKU; if your team needs AI in security operations, that is Security Copilot; and so on. The Microsoft Copilot brand does not mean a single licensing surface.

Admin/SSO availability, data-handling for AI inputs and outputs, conversation and document-content retention policy per tier, model-training opt-outs, region and currency, brand-voice and style-guide enforcement (Grammarly has style-guide and brand-voice features on Enterprise; Microsoft Copilot Business has admin templates and tenant grounding), and which features are entitled at each plan tier should all be confirmed on each vendor's official documentation before procurement. Treat each vendor's published policy as the only authoritative source on what is and is not used for model training or improvement.

Pricing and plan caveats

• Grammarly (AI): the page-body read of grammarly.com/plans on 2026-05-22 KST showed Free at $0/month with 100 generative-AI prompts per month plus core grammar and tone features, Pro at $12/month with 2,000 generative-AI prompts per member per month plus tone and rewrite suggestions, and Enterprise on Contact Sales pricing with unlimited generative-AI prompts and admin and security controls. Student/education discounts, region-specific pricing variants, and the exact Enterprise per-seat USD figure were not in scope of that fetch and should be confirmed on the official plans page or through Grammarly's sales channel before being quoted.
• Microsoft Copilot: the 2026-05-23 page-body read of microsoft.com/en-us/microsoft-365/copilot/business confirmed Microsoft 365 Copilot Business at $18/user/month with annual commitment paid yearly, $18.90/user/month with annual commitment paid monthly, and $25.20/user/month on a monthly commitment, each requiring a separate qualifying Microsoft 365 license. The 2026-05-23 read of microsoft.com/en-us/microsoft-copilot confirmed the free consumer Copilot at copilot.microsoft.com plus a free Microsoft Copilot app, and Microsoft 365 Copilot Chat at no additional cost for users with eligible Microsoft 365 subscriptions. Consumer Microsoft Copilot Pro USD pricing was not visible during the same fetch pass (multiple Copilot Pro URLs returned 403/404/timeout); Copilot Pro pricing should be verified directly on Microsoft's official Copilot Pro store/landing page before being quoted. Microsoft 365 Copilot Enterprise SKU and education SKU pricing were not in scope of the Business page fetch and should be confirmed through Microsoft's enterprise procurement surfaces.

Both vendors have moved SKUs, features, and quotas between releases. Treat the structural facts and numbers above as recent (May 2026) reference points, not as long-term guarantees. Re-verify before quoting either page in a high-stakes decision.

Who should choose Grammarly (AI)

• Your writers type meaningful prose across many apps every day — email (Gmail or Outlook), chat (Slack), documents (Google Docs, Word), CRM notes (Salesforce), social posts (LinkedIn), browser forms — and you want a single in-place writing layer that follows the writer between those apps with grammar, clarity, tone, and one-click rewrite assistance.
• You want an explicit per-tier generative-AI prompt cap (100 / 2,000 / unlimited) so finance can size the per-seat bill predictably.
• You want the buying motion to be a per-writer decision sized against communications, sales, customer-support, marketing-ops, or recruiting headcount — not a centralized IT / workplace-productivity rollout.
• You want a free evaluation surface at $0/month that is the same in-place writing assistant as Pro, just with a smaller generative-AI prompt cap.
• Your team's writing happens at least partly outside Microsoft 365 — meaning the in-Word/in-Outlook-only entitlement of Microsoft 365 Copilot Business would only cover part of the writing surface anyway.

Who should choose Microsoft Copilot

• Your organization already standardizes on Microsoft 365 and Windows; your users live in Word, Outlook, Excel, PowerPoint, and Teams every day; and the procurement, identity (Microsoft Entra), and compliance posture is easier to satisfy through Microsoft contracts than through a new vendor.
• You want admin tooling (Copilot Analytics, SharePoint Advanced Management, sensitivity labels) for AI adoption alongside the AI itself, and you want Entra-backed identity and conditional access in place from day one.
• Your team needs internal-document search across a Microsoft 365 tenant via Microsoft Graph (100+ connectors), grounded chat across that work data, custom agents with advanced reasoning, and Copilot Notebooks inside the Microsoft 365 Copilot Business SKU.
• A no-additional-cost evaluation surface matters to you: Microsoft 365 Copilot Chat is included for users with eligible Microsoft 365 subscriptions, so you can pilot the in-365 chat surface before committing to per-user Business pricing at $18/$18.90/$25.20 per user/month.
• You want AI-generated images, posters, banners, and videos as part of the same Business entitlement — meaning a single per-user line item covers more than just text drafting in Word and replies in Outlook.
• You accept that "Microsoft Copilot" spans multiple SKUs and that GitHub Copilot, Microsoft Security Copilot, Microsoft Copilot Studio, Copilot in Azure, and Copilot in Power Apps are sold separately and not covered by a Microsoft Copilot license.

Alternatives to consider

• Claude — fits when your daily work is reasoning-heavy reading and writing across long documents and you want a careful general-purpose chat assistant for the analytical pieces. Useful complement to either of these two when the long-form drafting job is not really in-app at all.
• Gemini — fits when your team's canonical documents live in Google Workspace rather than Microsoft 365; Gemini is the analogous large-vendor AI that lives inside Gmail, Google Docs, Drive, and Search. See Gemini vs Microsoft Copilot for the in-suite-vs-in-suite framing.
• Notion AI — fits when your team's canonical documents already live in a Notion workspace and you want AI drafting / summarization / Q&A inside that workspace rather than as a separate writing helper or a Microsoft 365 add-on. See Notion AI vs Microsoft Copilot for the cross-suite framing.
• GitHub Copilot — fits when your top need is AI inside the IDE for developers and teams whose repos live on GitHub. Sold separately from Microsoft Copilot even though both are Microsoft brands.
• Jasper — fits when the job is templated, brand-voiced marketing content at volume with team review, not general writing assistance or in-suite productivity AI. See Microsoft Copilot vs Jasper and Grammarly (AI) vs Jasper.
• ChatGPT — fits when you want the largest mainstream chat-assistant ecosystem of plugins, custom GPTs, and tutorial content alongside a general-purpose assistant that is not tied to a specific productivity suite or a specific writing-surface.

Bottom line

• Decide by what surface the writing actually happens on, not by which AI brand sounds more capable in marketing copy. Grammarly (AI) is an in-place writing layer that follows a writer across many apps (Gmail, Outlook, Google Docs, Word, Slack, Salesforce, LinkedIn, browser forms, mobile keyboards). Microsoft Copilot, in its M365 Copilot Business SKU, is the AI surface inside Microsoft 365 and Windows. Neither earns its line item from a buyer whose writing happens entirely on the surface the other product covers.
• If your team's serious writing is short-to-medium prose spread across many apps every day, default to Grammarly (AI). Free at $0/month with 100 generative-AI prompts per month is enough to evaluate; Pro at $12/month with 2,000 generative-AI prompts per member per month is the typical individual seat; Enterprise on Contact Sales is the per-seat sales motion for unlimited generative-AI prompts and admin and security controls.
• If your organization already runs on Microsoft 365 and Windows, default to Microsoft 365 Copilot Business at $18/$18.90/$25.20 per user/month depending on commitment, on top of a separate qualifying Microsoft 365 license. The distinctive value is AI inside Word, Excel, Outlook, PowerPoint, and Teams — plus admin tooling, Microsoft Graph search across work data (100+ connectors), Entra identity, AI-generated images / posters / banners / videos, and Copilot Notebooks. Consumer Microsoft Copilot Pro pricing and Enterprise / education SKU pricing should be verified directly on Microsoft's official surfaces.
• Do not expect either tool to do the other's job. Grammarly does not draft a whole document from a brief, recap a Teams meeting, or build an Excel formula. Microsoft Copilot does not appear inside Gmail, Google Docs, Slack, or Salesforce. Mixed organizations whose writers spread their writing across both Microsoft 365 and non-Microsoft apps often pay for both, sized to the populations that use each surface.
• Re-verify both vendors' pricing/plans pages directly before any team-level commitment; both have changed SKUs, plans, quotas, and feature bundles multiple times, Grammarly's Enterprise per-seat USD figure was not in scope of the 2026-05-22 fetch, and consumer Microsoft Copilot Pro USD pricing was not visible during the 2026-05-23 fetch.

Sources

• Grammarly AI feature page: https://www.grammarly.com/ai — recorded as src-grammarly-ai-2026-05-21 in data/sources.json with access_status = ok; cited here only as the official AI feature URL, no pricing or quota claim asserted from this source.
• Grammarly plans page: https://www.grammarly.com/plans — recorded as src-grammarly-plans-2026-05-22 in data/sources.json with access_status = ok after a 2026-05-22 page-body read; this is the source of every Grammarly plan, price, and per-tier generative-AI quota quoted on this page.
• Microsoft Copilot official homepage: https://copilot.microsoft.com/ — recorded as src-microsoft-copilot-needs-verify in data/sources.json with access_status = ok. The id carries a legacy needs-verify semantic from the seed scan, but the current access status is ok. Cited here only as the official Microsoft Copilot landing URL; the free consumer Copilot surface and multi-SKU brand context come from the supporting microsoft.com/en-us/microsoft-copilot page-body read on 2026-05-23, captured as part of the same source record.
• Microsoft 365 Copilot Business page: https://www.microsoft.com/en-us/microsoft-365/copilot/business — recorded as src-microsoft-365-copilot-business-2026-05-23 in data/sources.json with access_status = ok after a 2026-05-23 page-body read; this is the source of every Microsoft 365 Copilot Business plan, USD price, commitment-tier, qualifying-license requirement, and feature-bundle fact quoted on this page.

All four entries above resolve to official first-party URLs. Re-verify the two pricing/plans pages before any new pricing-sensitive quote. If a later refresh changes the access status of src-microsoft-copilot-needs-verify, this page does not need to be rewritten — it never asserts a fact from the homepage source beyond what is visible on it today.

Internal links

• /tools/grammarly-ai/
• /tools/microsoft-copilot/
• /ai-writing/
• /ai-assistants/
• /compare/notion-ai-vs-grammarly-ai/
• /compare/claude-vs-grammarly-ai/
• /compare/github-copilot-vs-grammarly-ai/
• /compare/grammarly-ai-vs-jasper/
• /compare/grammarly-ai-vs-replit-ai/
• /compare/claude-vs-microsoft-copilot/
• /compare/gemini-vs-microsoft-copilot/
• /compare/microsoft-copilot-vs-jasper/
• /compare/notion-ai-vs-microsoft-copilot/

Disclosure

• Affiliate links: none.
• Sponsored content: none. Neither Grammarly Inc. nor Microsoft has any relationship to this page.
• Generative AI assistance: this draft was assembled with the help of an AI assistant working from the HMP source records and the two qa_passed tool pages (tools/grammarly-ai.md, tools/microsoft-copilot.md).

Trademark notice

Grammarly is a trademark of Grammarly Inc. Microsoft, Microsoft 365, Microsoft Copilot, Microsoft 365 Copilot, Microsoft Copilot Studio, Microsoft Security Copilot, Microsoft Entra, Microsoft Graph, Word, Excel, Outlook, PowerPoint, Teams, SharePoint, OneDrive, Windows, Edge, and Azure are trademarks of Microsoft Corporation. GitHub and GitHub Copilot are trademarks of GitHub, Inc., a Microsoft subsidiary. Anthropic and Claude are trademarks of Anthropic. OpenAI and ChatGPT are trademarks of OpenAI. Notion is a trademark of Notion Labs. Jasper is a trademark of its operator. Google, Google Workspace, Gmail, Google Docs, and Gemini are trademarks of Google LLC. Slack and Salesforce are trademarks of Salesforce, Inc. LinkedIn is a trademark of LinkedIn Corporation, a Microsoft subsidiary. Cursor is a trademark of Anysphere. Use here is referential only and does not imply endorsement, partnership, or affiliation with any of these vendors.

Update log

• 2026-05-24 (draft): first local draft created from templates/comparison-page-template.md. Both source tool pages (grammarly-ai, microsoft-copilot) are qa_passed per content/content-status.json.
• 2026-05-24 (QA): independent Section B walk-through completed. B1 source quality (both compared tool pages are qa_passed; all four cited sources exist in data/sources.json with access_status = ok; ≥ 4 sources total; no needs_verification or blocked source is treated as fact — passed; src-microsoft-copilot-needs-verify carries a legacy "needs-verify" semantic in its id but its current access_status = ok and it is cited only as the homepage URL with no pricing/feature claim drawn from it; every Microsoft 365 Copilot Business plan/price/feature claim is drawn from src-microsoft-365-copilot-business-2026-05-23; every Grammarly plan/price/quota claim is drawn from src-grammarly-plans-2026-05-22). B2 decision clarity (Quick recommendation names a distinct situation per tool; Bottom line provides 5 decision rules; Grammarly pricing rows cite the 2026-05-22 source-read, Microsoft 365 Copilot Business pricing rows cite the 2026-05-23 source-read, Grammarly Enterprise per-seat USD figure and consumer Microsoft Copilot Pro USD pricing both routed to "verify on official site" — passed). B3 information density (≥ 900 words; use-case sections cover writing, coding/technical, research/fact-checking, and teams; comparison table separates source-backed fact rows from author-judgment rows via the Notes column — passed). B4 trust/safety/trademark/disclosure (no vendor disparagement; no false performance/accuracy/compliance guarantees; explicit "None of this is a benchmark claim" note in the coding/technical-work section; Trademark notice present and covers Grammarly, Microsoft and its M365 stack, GitHub, Anthropic, OpenAI, Notion, Jasper, Google/Gemini, Slack/Salesforce, LinkedIn, and Cursor; Disclosure block matches A5 — passed). B5 internal linking (13 internal links — passed). Cross-suite framing: the page is explicit that Grammarly (AI) is the in-place writing layer that follows a writer across many apps and Microsoft Copilot (in its M365 Copilot Business SKU) is the in-Microsoft-365 AI layer — they are partial substitutes only at the surface (both "AI for writing") and not for the deeper job each is sized for. content_status = qa_passed. Freshness: re-verify both vendors' pricing pages by 2026-08-20, which is 90 days from the older of the two pricing-page fetch dates (2026-05-22 for Grammarly).