Nogrammerly
Nogrammerly is a free MIT desktop writing assistant for Mac and Windows that underlines spelling, grammar and style problems in almost every app, with one-click rewrites and tone changes. The AI runs on the computer itself: Apple Intelligence on Mac, Phi Silica on Windows Copilot+ PCs. Without those capabilities, Nogrammerly still offers spelling, grammar and style checks from built-in rules.
What does Nogrammerly do?
Nogrammerly's README calls it "the free, open-source, 100% on-device Grammarly alternative for Mac and Windows." It underlines problems in any text field, in "almost every app" the README names: Slack, Teams, Mail, Outlook, Notes, Zoom and more. Right-click an underline to replace it, copy the suggestion, rewrite the sentence, ignore the issue or add the word to a dictionary. A floating button in the corner of each field rewrites a selection or the whole text as Professional, Friendly, Confident or Concise.
The AI parts (rewrites, tone changes) run on the device itself: Apple Intelligence on macOS 26 or later, Phi Silica on Windows Copilot+ PCs. The README says that without AI hardware, "you still get spelling, grammar and style checks" from the operating system's own checker and built-in rules. A live issue count sits on the field button and in the menu bar or notification area; on Mac there is also a built-in writing editor with a writing score, a tone picker and a Rewrite button.
Key facts
- Licence: MIT, per the README's own badge.
- macOS: 14 (Sonoma) or later on Apple Silicon; macOS 26 or later with Apple Intelligence turned on for AI checks and rewrites.
- Windows: 10 and 11 x64, plus an Arm64 build for Snapdragon Copilot+ PCs; marked beta in the README.
- The Mac installer is 4 MB; the Windows installer is about 110 MB, per the README.
- Permissions needed on Mac: Accessibility (System Settings, Privacy & Security).
- Where it runs: every spell check, built-in style rule and AI rewrite is performed on the computer; the README says "your writing never leaves your device."
- The Mac build is not notarised by Apple, so the first launch needs the Open Anyway step in System Settings.
What does it replace, and where does it fall short?
Nogrammerly replaces Grammarly for someone who wants grammar, spelling and tone fixes across every app on their desktop, with no account, no subscription, and no cloud upload. It is a candidate on the open-source alternatives to Grammarly page.
Where it falls short: the AI rewrites and tone changes need Apple Intelligence (macOS 26 or later on an eligible Apple Silicon Mac) or Phi Silica (Windows Copilot+ PCs); without that hardware, you get the rule-based checks only. The README does not promise a browser extension for arbitrary websites; it works through accessibility APIs in native apps and web browsers. For a browser-first checker, SafeTyper; for a code-editor-first grammar checker, Harper.
How does Nogrammerly run?
On Mac, download the DMG from Releases and drag Nogrammerly to Applications. Open it, use the Open Anyway path in System Settings on the first launch since it is not notarised, and follow the setup window to grant Accessibility access. On Windows, download the x64 or Arm64 ZIP and run the installer. The README lists no sign-in step; the AI model is already on the device.
The README describes no hosted or paid tier. Nogrammerly is distributed as a desktop app with the full source available under MIT.
Who is Nogrammerly for?
A Mac or Windows user with a recent on-device AI stack who wants grammar, spelling and tone changes in every app without a Grammarly plan. A reader on a browser-first workflow or on an older Mac without Apple Intelligence should pick a different project.
What limits does the README state?
- The Windows build is marked "beta".
- AI rewrites and tone changes need Apple Intelligence (macOS 26 or later on Apple Silicon) or Phi Silica (Windows Copilot+ PCs).
- The Mac build is not notarised by Apple; the first launch needs the Open Anyway step.
- Accessibility access is required on Mac so the app can read the text in each field.
Questions people ask
Is Nogrammerly open source?
Yes. The README's badge is MIT, and the LICENSE file carries the MIT text. MIT is an OSI-approved licence with no added conditions, so you can read, change and ship your own build. The project has no paid tier.
Does Nogrammerly need an internet connection?
No. The README says "Nogrammerly runs spell checking, rules and on-device AI on your Mac or PC, and nothing is sent over the network." Spelling and rule-based checks work on any supported machine, and the AI rewrites run on Apple Intelligence or Phi Silica, both of which are on the device.
Which Macs and PCs can run Nogrammerly?
Mac: macOS 14 (Sonoma) or later on Apple Silicon; macOS 26 or later with Apple Intelligence turned on for the AI parts. Windows: 10 or 11 x64, with an Arm64 build for Snapdragon Copilot+ PCs; the Windows build is marked beta in the README.
How does Nogrammerly compare with Grammarly?
Grammarly is a hosted service that sends what you type to its servers and runs its own writing models. Nogrammerly runs on the device with the OS's own model and style rules, and the code is MIT. The open-source alternatives to Grammarly page lists more candidates.
Does Nogrammerly work in a browser?
The README describes Nogrammerly as working wherever the accessibility API can read text, which includes most native desktop apps and browser text fields. The project is not published as a browser extension; for a browser-extension approach, SafeTyper is on the Grammarly alternatives page.
Sources
- Nogrammerly README: github.com/gaurabh-pei/nogrammerly, read 2026-10-19.
- Nogrammerly LICENSE (MIT): github.com/gaurabh-pei/nogrammerly/blob/main/LICENSE, read 2026-10-19.
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Added October 19, 2026. Every claim above comes from the project's README, LICENSE or model card, read on October 19, 2026, or from the GitHub API on the date shown in the panel. Found an error? Write to reveneau@licheo.com and it is fixed in the next weekly pass. Repository: github.com/gaurabh-pei/nogrammerly.
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