AI Grammar Checker & Rewriter - Polish Your Writing
Fix grammar mistakes, improve sentence clarity, and adapt your writing tone - powered by a rules engine built into your browser.
How to use AI Grammar Checker in 3 simple steps
Enter Text
Type or paste up to 3,000 characters of text into the input box.
Select Mode
Choose your desired goal: Fix Grammar, Improve Clarity, Formal Tone, Friendly Tone, or Shorter.
Review & Copy
Inspect the polished output, compare improvements, and copy with a single click.
Something not working?
Found a bug in AI Grammar Checker or have an idea that would make it better? Email me directly and I'll take a look.
Email me directly coderbt66@gmail.comNo account and no uploads — your message is sent through your own email app.
Intelligent AI Proofreading and Text Refinement
Clear, error-free communication is essential for professional emails, cover letters, essays, and marketing copy. A misplaced comma or awkward phrasing can undermine the authority of an otherwise compelling argument.
Toolnova AI Grammar Checker & Rewriter analyses syntax, subject-verb agreement, punctuation, and stylistic flow. When an AI endpoint is configured it runs through a secure Cloudflare Edge Worker; on the static deployment the same five modes run through a built-in rules engine, so you always get a result without uploading your text.
Select from five targeted refinement modes: quickly correct grammatical slips, elevate clarity, adapt text for executive correspondence with Formal mode, soften messages with Friendly mode, or trim wordiness with Shorter mode.
Key features & capabilities
Frequently asked questions about AI Grammar Checker
Common questions about usage, privacy, limits, and browser compatibility.
Is the AI grammar checker private?
The tool tries the AI endpoint first. When one is configured, text travels over an encrypted HTTPS connection to a stateless Cloudflare Edge Worker that does not store it in a database. When no endpoint is available, the checker switches to a built-in rules engine that runs entirely in your browser, so nothing is transmitted at all.
How much text can I check at one time?
Each run accepts up to 3,000 characters, roughly 500 words or a one-page letter. Longer documents like essays or reports need to be pasted in sections and checked one part at a time. Working in sections also makes it easier to review each change before moving on.
What do the five writing modes do?
Fix Grammar corrects agreement, punctuation, and similar errors while leaving your wording largely intact. Improve Clarity untangles awkward sentences, Formal and Friendly shift the tone, and Shorter trims wordiness. Choosing the mode that matches your goal gives a far more predictable result than trying every option.
Can it check text that isn't in English?
English is where the checker performs best, including both American and British spelling conventions. Other languages may receive partial corrections, but the grammar rules and tone modes are built around English usage. For non-English writing, treat the output as a rough suggestion rather than a final edit.
Will it rewrite my text and change my meaning?
The tool edits within the mode you select, so a grammar pass stays close to your original phrasing while the tone and brevity modes make larger changes. The output appears next to your original text, which lets you compare and copy only what you want. Keeping a copy of your draft is still the safest habit before replacing anything.
Is the grammar checker free, and do I need an account?
The checker is free to use without an account, signup, or payment, and there are no watermarks on the text you receive. Requests are rate limited to keep the service available for everyone, so very rapid repeated checks may be throttled. If that happens, wait a moment and run the check again.