GemType
GemType is a free, open-source Grammarly alternative under Apache 2.0. It runs as a Chrome, Edge and Firefox extension, a Microsoft Word add-in, and a menu-bar or tray app that works in any desktop program through a global hotkey. It uses your own free Google Gemini API key, so your text goes straight to Google and never through a server run by the project.
What does GemType do?
GemType is described in its README as "a free, open-source Grammarly alternative for your browser, Microsoft Word, and the whole desktop, powered by your own Gemini API key." It underlines grammar and spelling issues about a second after you stop typing in any text field, and one click accepts the fix. A floating toolbar lets you rewrite selected text with Improve, Fix, Shorten, Formal and Casual actions, which are also on the right-click menu.
The README says text is sent only to Google's Gemini API using your own key, with no middleman server, no tracking and no analytics. Sites can exclude a field with a data-gemtype="false" attribute, and users can turn checking off per site or globally.
Key facts
- Licence: Apache 2.0, one licence for the whole project.
- Surfaces: Chrome, Edge and Firefox extensions on their respective stores; a Microsoft Word Office task-pane add-in in the
msword/directory; and a menu-bar or tray app for macOS, Windows and Linux that works in any app through a global hotkey. - Bring your own key: uses your own Google AI Studio Gemini key, which the README links as free with no card required.
- Any language, auto-detected by the model.
- Sentence verification: after every accepted fix, the surrounding sentence is re-checked, so word-level fixes do not leave broken sentences.
- Preset rewrite styles: Improve, Fix, Shorten, Formal, Casual, per the README.
- The Safari build exists but is not shipped: the README says it needs the Apple Developer fee and is waiting on a sponsor.
- iOS and Android keyboards are planned, per the README.
What does it replace, and where does it fall short?
GemType replaces Grammarly for grammar and spelling on the web, in Microsoft Word, and in any desktop program that accepts a keyboard shortcut. It is a candidate on the open-source alternatives to Grammarly page.
Where it falls short: the README says Google Docs is "not supported (Google whitelists specific vendors)". There is no Safari build on the App Store yet. iOS and Android keyboards are only planned. And every check sends the text you type to Google, using your key. For a fully local option, see Harper or LanguageTool.
How does GemType run?
The browser build installs from the Chrome Web Store, Edge Add-ons, or Firefox Add-ons in one click. After install, you paste a free Google Gemini API key from Google AI Studio into the extension's settings. A manual developer-mode install from this repository is also documented in the README.
The Word add-in lives in msword/ and installs as an Office task pane. The desktop tray app is on the project's releases page, works through a global hotkey in any application, and is available for macOS, Windows and Linux. There is no hosted paid version and no account.
Who is GemType for?
Someone who writes across Gmail, LinkedIn, Word, and other desktop apps and wants a fix-my-writing shortcut without a subscription, and who is willing to bring their own Google Gemini key. A team that needs Google Docs coverage, or that cannot send text to Google under its own policy, should look elsewhere.
What limits does the README state?
Google Docs is not supported, because Google whitelists specific vendors. Safari is build-ready but is not shipped without an Apple Developer fee, so it depends on a sponsor. iOS and Android keyboards are planned rather than released. All checks go to Google's Gemini API with your key, so Google receives the text you type in the fields it watches.
Questions people ask
Is GemType open source?
Yes. The whole project is Apache 2.0, an OSI approved licence, with no separate licence on the extension, the Word add-in or the desktop app. You can read, modify and redistribute the code under Apache 2.0 terms, including for commercial use, with attribution.
Does GemType work without a subscription?
Yes. The README says GemType is free and uses your own Google Gemini API key from Google AI Studio, which has a free tier with no card required. The README says a single writer will normally stay inside the free quota because GemType checks only after you pause, skips unchanged text and caches results.
Where does the text go when GemType checks it?
To Google's Gemini API, using your own API key, and nowhere else. The README says there is no middleman server run by GemType, no tracking and no analytics. For a tool that keeps the text on your own machine, see Harper.
Does GemType work in Google Docs?
No. The README says it is not supported, because Google whitelists specific vendors for the Docs editing surface, so a third-party extension cannot read or write the document. Other options are on the open-source alternatives to Grammarly page.
Does GemType work on Safari?
Not yet on the App Store. The README says the Safari build is ready but has not shipped because it needs the Apple Developer fee, and the project is asking for a sponsor. Chrome, Edge and Firefox are supported today, and the desktop tray app covers Safari indirectly through a global hotkey.
Sources
- GemType README and LICENSE: github.com/riponcm/GemType, read 2026-09-28. The README describes the browser, Word, and desktop builds and the free-key model.
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Added September 28, 2026. Every claim above comes from the project's README, LICENSE or model card, read on September 28, 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/riponcm/GemType.
Running one of these inside your own environment, with your own data and your own security rules, is the kind of work Reveneau does. Read how a forward deployed engagement works.