Grammar, spelling and punctuation

AI grammar checker free to join, paid by the word

Paste up to 3,000 words in English, German, Japanese, Chinese, Spanish or French. You get the corrected text back with a numbered list of the main fixes, so you can see what changed and why.

  • Six languages
  • Fixes explained in English
  • Price shown before you check
Language
Depth
0 / 3,000 words

Corrected text

Paste your text and press Check grammar. The corrected text and the main fixes appear here.

At a glance

Grammar Checker AI is an AI grammar checker for English, German, Japanese, Chinese, Spanish and French: free to join, paid per word. Paste 1 to 3,000 words, choose the language and a depth (proofread fixes errors only; polish also smooths awkward sentences), and get the corrected text with up to 12 main fixes explained in English. Checks use purchased credits at 1 credit per word ($0.08 to $0.20 per 1,000 words), with a 20-credit minimum; new accounts include no credits.

What it does
Corrects grammar, spelling and punctuation, then lists the fixes
Price
1 credit per word, 20-credit minimum; $0.08 to $0.20 per 1,000 words
Account
Free to sign up; checks use purchased credits
Text length
1 to 3,000 words per check
Languages
English, German, Japanese, Chinese, Spanish and French
Depth
Proofread (errors only) or polish (errors and clarity)
Model
Claude Haiku 5.5 with our proofreading rules

What you get from each check

A grammar checker should show its work. Each check returns the corrected text first and the reasons after it.

  • 01

    Corrected text, ready to copy

    Your whole text comes back with the errors fixed, in the same paragraphs and line breaks, so you can paste it straight back where it came from.

  • 02

    The main fixes, explained

    Up to 12 numbered fixes, each with the original words, the correction and a short reason in English, so every change can be checked and learned from.

  • 03

    Six language settings

    English, German, Japanese, Chinese, Spanish and French, each with its own checklist: cases and verb position in German, particles in Japanese, 的, 地 and 得 and measure words in Chinese.

  • 04

    Proofread or polish

    Proofread fixes errors and leaves correct sentences alone. Polish also smooths awkward or unclear sentences while keeping your voice, structure and meaning.

  • 05

    Your content stays yours

    The checker is told to keep names, numbers, quotations, links and technical terms, and not to translate, summarize or add ideas. Instructions inside your text are to be corrected, not followed.

  • 06

    The price before you check

    The credit cost appears as you paste: 1 credit per word, at least 20 credits. If a check fails, its credits return to your balance automatically.

How to check grammar online

  1. 01

    Paste your text

    Paste 1 to 3,000 words: an email, an essay, a report, a message or a page of notes.

  2. 02

    Choose language and depth

    Pick the language the text is written in, then proofread for errors only or polish for errors and clarity.

  3. 03

    Review the fixes

    Read the numbered fixes, copy the corrected text, and undo anything that changed what you meant.

What a grammar check covers here

A grammar check looks for the mistakes a careful editor would mark and leaves everything else alone. Grammar Checker AI covers:

  • Spelling and typos, including words that are spelled right but wrong in context, such as their, there and they're
  • Grammar: agreement, tenses, articles, word forms, cases and word order
  • Punctuation and capitals: commas, apostrophes, quotation marks, and full-width marks in Chinese and Japanese
  • With polish only: awkward phrasing, unclear references, inconsistent terms and needless repetition

Free AI grammar checker: what costs nothing here

Creating an account costs nothing, and neither does anything you can read on this site: the lists of common mistakes in English, German, Japanese and Chinese, the punctuation rules and the proofreading prompt for ChatGPT.

Automated checks are paid from the first one. New accounts start with no credits; a check costs 1 credit per word with a 20-credit minimum, so a 3,000-word check costs $0.25 to $0.60 depending on the pack or plan. Credits come from one-time packs (from $4.99) or monthly plans (from $7.99).

How the checker works

Your text goes to Claude Haiku 5.5, a fast language model made by Anthropic, through a commercial model API, together with our proofreading rules: what to correct, what to keep exactly as written, a checklist for the language you chose, and the shape of the answer.

The rules ask for the corrected text first and a numbered list of the main fixes after it, in plain text. They treat your text as data: a question or instruction inside it is to be corrected like any other sentence, not answered or followed.

A free checklist before you hit send

Four habits that catch what any checker can miss:

  • Read the text aloud once; your ear catches missing words that your eyes skip.
  • Check every name, number and date against your source.
  • Search for the words you often confuse, such as its and it's.
  • Keep each sentence to one main idea when the subject is hard.

What no grammar checker can promise

AI proofreading works from patterns, so it can go wrong where the right answer depends on context it cannot see: a deliberate style, a quotation, a brand name, a technical term or a regional variety. Review each listed fix, keep what helps and undo what changes your meaning. For legal, medical or published work, a human editor is still worth it.

Ways to check grammar, compared

Grammar Checker AISpell check in your editorAsking a chatbot
What it checksSpelling, grammar and punctuation; clarity with polishMostly spelling; some editors flag grammarWhatever your prompt asks for
Shows what changedUp to 12 main fixes with reasonsUnderlines, one at a timeOnly if you ask for a list
Leaves correct text aloneProofread changes errors onlyYes, it only suggestsDepends on the prompt
LanguagesSix settings with language checklistsThe dictionaries you installMany, depending on the model
Cost$0.08 to $0.20 per 1,000 wordsIncluded with the editorFree or paid plans, by provider

Frequently asked questions

Is this AI grammar checker free?

Signing up is free, and the guides and mistake lists on this site are free to read. Automated checks use purchased credits: 1 credit per word with a 20-credit minimum per check. New accounts start with no credits; packs start at $4.99 for 25,000 credits and plans at $7.99 a month.

How accurate is the grammar check?

We publish no accuracy rate, because we have not measured one we could stand behind. The checker is built to fix errors and leave correct text alone, but like any grammar checker it can miss a mistake or change something that was right, especially names, technical terms, dialect and deliberate style. Every main fix is listed with its reason, so you can review it.

Which languages can it check?

Six: English, German, Japanese, Chinese, Spanish and French, each with its own checklist. Choose the language before you check. If the text turns out to be in another language, the checker is told to correct it in the language it is written in and to say so at the top of the list of fixes.

What is the difference between proofread and polish?

Proofread corrects errors and nothing else, so correct sentences stay exactly as you wrote them. Polish also fixes sentences that are hard to read, such as awkward word order or a wrong word for the context, while keeping your voice, meaning and structure.

Will it rewrite my whole text?

No. It is told to change only what is wrong (and, with polish, what is clearly hard to read), to keep your names, numbers and quotations, and not to translate or summarize. Every main fix is listed, so you can see what changed.

How long can my text be?

From 1 word up to 3,000 words per check; each Chinese or Japanese character counts as one word. Split longer documents into sections, which also keeps the list of fixes easy to review.

Do you store my text?

Your texts and results are stored so you can see your history, and each text is sent to the model provider only to run your check. We do not sell your text or use it to train models. You can ask us to delete your account and its history from the email address on your account.

Check your next text before you send it

Pick a pack from $4.99 or a plan from $7.99 a month. Signing up is free; checks use purchased credits.

Last updated October 23, 2026

Create your Grammar Checker AI account