Free Grammar Checker Online — AI-Powered, No Sign-up to Start
Grammarly is the default grammar checker. It works. It also wants $12-30/month, asks you to install a browser extension that watches every text field, and pushes its premium tier hard.
AI Pass Grammar does the same job — fix grammar, fix typos, suggest clearer phrasing, adjust tone — without the extension and without the subscription.
The 30-second flow
- Open aipass.one/apps/grammar
- Paste your text into the box
- Click Check
- Review the suggested edits, accept or reject
- Copy the cleaned version. Try it now.
No browser extension. No tracking on every text field. The text you paste only goes to the model when you hit Check.
Why it's actually free
Sign up = $1 of credit in your wallet. Grammar checks run on a small LLM and are billed per request — typically a fraction of a cent per check. A dollar covers hundreds of checks before you'd ever need to top up. Credit doesn't expire. No subscription.
What the AI grammar checker actually catches
- Hard grammar errors — subject-verb agreement, tense slips, missing words
- Typos — even ones spell-check misses (homophones, doubled letters)
- Punctuation — comma splices, missing Oxford commas, run-ons
- Clarity — wordy phrasing rewritten in fewer words
- Tone — make it more formal / casual / direct, on request
- Passive voice — flagged with active alternatives
- Sentence structure — overlong sentences split, choppy ones combined
How it stacks up vs the alternatives
| AI Pass Grammar | Grammarly Free | Grammarly Premium | ChatGPT | |
|---|---|---|---|---|
| Cost | Free + tiny pay-per-check | Free with limits | $12-30/mo | $20/mo |
| Sign-up | $1 credit on signup | Account required | Account + paid | Account + paid |
| Browser extension required | No | Yes (or web app) | Yes | No (web app) |
| Tracks every text field | No | Yes (extension) | Yes (extension) | No |
| Tone adjustments | Yes | Premium only | Yes | Yes |
| Clarity rewrites | Yes | Premium only | Yes | Yes |
| Word-count cap | None | None on web app | None | Daily message cap |
| Custom style guides | No | No | Yes (Business) | Via prompt |
When the alternatives win
- Grammarly Premium — if you want a single tool that integrates with Word, Outlook, Google Docs, and watches your tone in real time as you type. The deep integration is genuinely useful for professional writers.
- Grammarly Free if your editing is mostly catching typos and you don't mind the extension.
- ChatGPT if you're already there and want a single thread for writing, research, and code. Just ask "rewrite this for clarity."
- Hemingway Editor if you specifically want sentence-complexity coaching.
When the lighter tool wins
- You don't write enough to justify $12-30/month. Pay only for the checks you actually run.
- You don't want a browser extension watching every text field you type into.
- You want to paste a finished draft and get one cleanup — not real-time correction as you type.
- You're writing in spurts — a few hours one weekend, nothing for a month — pay-per-check fits the rhythm.
Try it now
Open AI Pass Grammar, paste a paragraph, click Check. The first hundreds of checks are on the house.