AI Grammar Checker
Fix grammar, spelling, and punctuation errors instantly — free, no account required, and nothing leaves your device. The AI model runs entirely in your browser.
How It Works
Paste your text
Drop in any writing — emails, essays, reports, or messages. Up to 3,000 characters. Nothing is sent anywhere.
Click Check Grammar
On first use, your browser downloads the AI model (~60 MB) once and saves it locally for instant reuse.
AI corrects locally
The T5 model runs right here in your browser — not on a server. Grammar and spelling are fixed in one pass.
Copy or download
Copy the corrected text to your clipboard in one click, or save it as a .txt file.
How to Check Grammar Online with AI
- Paste or type your text into the input area — emails, essays, reports, or any writing up to 3,000 characters.
- Click Check Grammar. On first use, a one-time model download (~60 MB) is required — your browser saves it locally for instant reuse.
- The AI applies the T5 grammar correction prefix and generates the corrected text in one pass. For texts over ~150 words the tool splits the input into chunks automatically.
- Click Copy to copy to your clipboard, or Download .txt to save the corrected text as a file.
Features
- Your text stays private: The AI model runs entirely in your browser — nothing is uploaded, stored, or shared.
- No account required: Open the page and start checking straight away.
- Grammar, spelling, and punctuation: T5-small fixes errors across all three in a single forward pass.
- Automatic chunking: Texts over ~150 words are split into segments, each corrected, then joined into a single output.
- Works offline: After the one-time model download, the tool runs with no internet connection.
- Flexible output: Copy corrected text to your clipboard or download it as a plain .txt file.
- Powered by T5-small: A lightweight encoder-decoder model by Google that corrects grammar in one pass. One-time download of ~60 MB.
Frequently Asked Questions
Is my text uploaded to your servers?
No. Your text never leaves your device. The entire process runs inside your browser — nothing is sent to or stored on any server.
Is this free to use?
Yes, completely free. No account required, no usage limits, and no hidden charges.
Why is the first grammar check slow?
The first time you use the tool, your browser downloads the AI model (~60 MB). After that one-time download, the model loads instantly from local storage and the tool works offline too.
What is the maximum text length?
Up to 3,000 characters. For texts over ~150 words the tool automatically splits the input into chunks, corrects each one, then joins them into a single corrected output.
Does it work offline?
Yes. After the model is downloaded on your first use, it is saved to your browser's local storage. You can then check grammar with no internet connection.
Which AI model does this use?
T5-small by Google — a lightweight encoder-decoder sequence-to-sequence model. It runs with the standard T5 grammar task prefix ("grammar:") and corrects errors in one forward pass. It is served as a quantized ONNX model via Transformers.js and runs in a Web Worker in your browser. The one-time download is ~60 MB.