Grammar Checker

What the grammar checker does

Typos and slips are easy to miss in your own writing because you read what you meant, not what you typed. The grammar checker reads what is actually there. It fixes spelling, grammar, punctuation, agreement and word choice, and it tells you what it changed and why, so a cover letter or an important email goes out clean.

The checking is done by Grok 4.20. It has been instructed to keep your meaning, your voice and your formatting, and to leave correct sentences alone. If your text has no mistakes, it says so and hands it back unchanged instead of rewriting it for the sake of change.

How to check your text

1. Paste the text into the box: an email, a paragraph of an essay, a social post, a form answer.
2. Choose how much to change. Only clear mistakes corrects definite errors and nothing else. Mistakes and clarity also rephrases clumsy or confusing sentences without changing what they mean. Full edit adds smoother flow and trims wordy passages, while keeping your own voice.
3. Choose what to show. Fixed text + list of changes puts the corrected version first and then quotes each change with a short reason. Fixed text only gives you a clean copy to paste. Explain each mistake is meant for language learners: every error comes with the rule behind it in simple words, and the corrected text follows.
4. Press Generate or Ctrl+Enter. Copy the result, regenerate, or use Continue in chat to ask about a particular correction.

Tips for proofreading with AI

• Start with the lightest level. Only clear mistakes changes the least, which makes it the safest choice for formal documents where every word was chosen on purpose.
• Read the list, not just the result. The reasons tell you which corrections you agree with. Grammar has gray areas, and some changes are style preferences.
• Learn from repeat errors. If the same rule keeps showing up, switch to Explain each mistake once and read the explanation properly.
• Check names and terms yourself. Unusual surnames, brand names and technical terms sometimes get "corrected" when they were right.

Example from a real run

We tested the tool with a Spanish sentence containing three mistakes, using the default settings:

Ayer yo fuí al mercado con mi hermana y compramos muchas frutas que estaba muy frescas. Después hemos ido a casa de mis abuelos, pero ellos no estaba.

The explanations came back in Spanish, the language of the text, which is how the tool is set up. A language teacher might also question mixing "fui" and "hemos ido" in the same story; at the lightest level, the checker left that style choice alone.

What it cannot do

• It is not infallible. Like any AI, it can miss an error or flag a correct sentence. For a thesis, a published book or a legal document, a human proofreader is still worth it.
• Regional spelling. It usually follows the spelling your text already uses, such as British or American English, but say so in the chat if a specific standard matters.
• Facts are not checked. A sentence can be grammatically perfect and wrong. Proofreading looks at language, not truth.
• Sensitive text. Your text is sent through our server to the model provider. Remove personal details from documents such as medical letters before pasting.

Grammar Checker FAQ

Which languages does it check?

Any language Grok handles well, including Spanish, French, German, Polish, Indonesian and Russian. Explanations come in the same language as your text.

Is it free to use?

Yes. Each check takes one of your 30 free messages a day, which are shared between the chat and every tool on the site. No account is needed.

Will it change my writing style?

Not at the first level. Only the Full edit level touches flow and wordiness, and even then it is told to keep your voice. If you want a real rewrite, the Paraphraser is built for that.

Can I check a long document?

Check it in sections that fit under the counter. Results are also easier to review a few paragraphs at a time.

Can I ask why a rule works the way it does?

Yes, in the chat. Continue in chat keeps the context, or start fresh with a proofreading prompt. Students may also like our guide to AI for students.