A grammar checker is worth running on anything someone else will read: a cover letter, a message to a client, a college essay, an eBay listing, a post in a neighborhood group. Paste the whole text and get it back with spelling, grammar and punctuation fixed. Sentences that are hard to follow come out clearer, but the meaning and your way of writing stay the same. Think of it as a proofread, not a rewrite.
Instead of underlining words one at a time, it reads the full text and returns a clean version you can copy straight away. That suits the most common case: you wrote something in a hurry and want it right before you hit send. If you want to see what changed, put it next to your original before you copy it.
It works in the language you wrote in. English is the obvious one, but Spanish, Portuguese, French, German, Italian and many other languages work too, and nothing gets translated. That helps if English is your second language and you write in both: paste either one.
What it fixes: typos, misspelled words, wrong verb forms, agreement, missing or extra commas, capital letters at the start of sentences and in names, and clumsy phrasing. What it leaves alone: facts, names, numbers, links and the tone you chose. It won't turn a casual note into a formal letter or cut it in half; for that, the paraphrasing tool can make a text shorter, friendlier, simpler or more formal.
You can check up to 50,000 characters at once, about 20 pages. An email or a message takes a few seconds; a long document takes a little longer. AI does the checking, so read names, technical terms and quotes once more before you send anything important.
The text is corrected on our server and is not stored there. The corrected version is saved in your library, only in this browser, so you can come back to it later on the same device. Looking for a plain spell checker? The spell checker page runs the same tool and gives the same result; it just answers the questions people usually have about spelling.