Microsoft Copilot or Grammarly?
Choose Microsoft Copilot when word, excel, powerpoint, outlook and microsoft 365 workflows is the closer match. Choose Grammarly when editing, rewriting and communication assistance across apps matters more. Test both on the same real tasks before moving a production workflow.
Word, Excel, PowerPoint, Outlook and Microsoft 365 workflows
Editing, rewriting and communication assistance across apps
Microsoft Copilot
Word, Excel, PowerPoint, Outlook and Microsoft 365 workflows
Official specification ↗Grammarly
Editing, rewriting and communication assistance across apps
Official specification ↗Side-by-side comparison
| Category | Microsoft Copilot | Grammarly |
|---|---|---|
| Provider | Microsoft | Grammarly |
| Type | Product · Productivity | Product · Writing |
| Pricing summary | Free options; Microsoft 365 Personal $9.99/mo; Premium $19.99/mo in US reference | Free and paid individual, business and enterprise plans |
| Input price | Product or plan pricing | Product or plan pricing |
| Cached input | Not directly comparable | Not directly comparable |
| Output price | Product or plan pricing | Product or plan pricing |
| Context window | Varies by included model and plan | Varies by included model and plan |
| Maximum output | Varies by included model and surface | Varies by included model and surface |
| Knowledge cutoff | Model-dependent; web access may add current information | Model-dependent; web access may add current information |
| Reasoning | Varies by selected model or mode | Varies by selected model or mode |
| Relative speed | Varies by model, plan and workload | Varies by model, plan and workload |
| Input modalities | See documented product features | See documented product features |
| Output modalities | See documented product features | See documented product features |
| Tools and integrations | Web-grounded Search and Deep Research; Memory, Actions and Copilot Vision; Word, Excel, PowerPoint, Outlook and Teams workflows; Microsoft Graph and Windows integration | Grammar, clarity and tone suggestions; Generative rewriting; Browser and document integrations; Style guides and organization controls |
| API / access | Product surface; see official source for API availability | Product surface; see official source for API availability |
| Best fit | Word, Excel, PowerPoint, Outlook and Microsoft 365 workflows | Editing, rewriting and communication assistance across apps |
| Company | Microsoft | Grammarly |
| Product category | Product · Productivity | Product · Writing |
| Current pricing note | Free options; Microsoft 365 Personal $9.99/mo; Premium $19.99/mo in US reference | Free and paid individual, business and enterprise plans |
| Best suited to | Word, Excel, PowerPoint, Outlook and Microsoft 365 workflows | Editing, rewriting and communication assistance across apps |
| Key capabilities | Web-grounded Search and Deep Research; Memory, Actions and Copilot Vision; Word, Excel, PowerPoint, Outlook and Teams workflows; Microsoft Graph and Windows integration | Grammar, clarity and tone suggestions; Generative rewriting; Browser and document integrations; Style guides and organization controls |
| Last verified | 2026-08-24 | 2026-09-02 |
| Official product source | https://www.microsoft.com/microsoft-365-copilot/pricing/individuals | https://www.grammarly.com/plans |
How we reached this verdict
We looked at the things that affect everyday use: what each product can do, how its plans are structured, where it fits into your existing workflow, and what the provider currently documents. Benchmark results are useful context, but they are not a universal winner score because test settings and tools vary.
Common questions
Microsoft Copilot or Grammarly: which should I choose?
Choose Microsoft Copilot for word, excel, powerpoint, outlook and microsoft 365 workflows. Choose Grammarly for editing, rewriting and communication assistance across apps. Validate the decision with your own prompts and total task cost.
Is Microsoft Copilot cheaper than Grammarly?
Pricing units can differ. Microsoft Copilot: Free options; Microsoft 365 Personal $9.99/mo; Premium $19.99/mo in US reference. Grammarly: Free and paid individual, business and enterprise plans. Check tool charges, plan limits, caching and long-context rules before comparing totals.
Which is better for coding and agent work?
Capability depends on the selected product surface, tools and harness. Microsoft Copilot is positioned for word, excel, powerpoint, outlook and microsoft 365 workflows; Grammarly is positioned for editing, rewriting and communication assistance across apps. Run the same repository task on both.
How do their context windows compare?
Microsoft Copilot lists Varies by included model and plan; Grammarly lists Varies by included model and plan. A larger limit does not by itself guarantee better retrieval or lower cost.
Official sources
Use these provider pages to confirm current features, pricing and availability.
AI tools change quickly. We checked this page on 2026-09-08. Before you subscribe, confirm the latest price, regional availability and usage limits on the provider website.