A grammar check that stays on your device.
Check English grammar, spelling and punctuation in your browser with Harper, choose each fix yourself, and keep your writing on your own device.
By Suraj Kumar3 min read
Most grammar checkers send what you write to a server. This one runs in your browser, so a letter, a report or a diary never leaves your device.
Paste, check, choose.
Paste or type your text and press Check spelling and grammar. Each problem is listed with Harper's reason and its fixes, such as has to have after I, or a to an before apple. Nothing changes until you press a fix; each fix is one step that Undo takes back, and Ignore hides a problem you disagree with.
Harper, on your device.
The checker is Harper, an open-source set of rules from Automattic. Its file (8 MB) is fetched once from this site when you first press Check and kept by your browser; after that it works without a connection. It checks English only, in American, British, Australian, Canadian or Indian spelling.
Harper is rules, not a language model: it is fast and keeps to what it knows, but it catches fewer problems than the large online checkers, can flag what is right, and does not rewrite your style. Read your text over too.
Nothing leaves your browser.
Everything is worked out on your device: what you paste, type or open is never sent anywhere, and nothing is kept when you leave the page. There are no adverts, no accounts and no limits on length.
Further reading
Topics: grammar checker · free grammar checker · private grammar checker · grammar check online · punctuation checker
A little less theory. A little more doing.
Try it on your own terms, with a free browser tool.
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