Check English grammar and spelling in your browser
LocuText helps you find common English grammar and spelling issues while keeping your draft in your browser. You decide which suggested edits to accept, reject, or change yourself.
Content reviewed:
What the English grammar checker does
Quick check uses the local Harper engine to flag spelling, common grammar patterns such as some article mistakes, and punctuation or usage issues. It works without downloading an AI model. You can also check a draft that mixes English and Chinese; the Chinese quick-check rules cover a limited set of common typos, grammar patterns, and formatting issues.
No checker catches every error. Names, technical terms, and unusual phrasing may need your judgment, and some suggestions may be wrong. The default MacBERT model is for Chinese character corrections, not a full Chinese grammar checker. An optional local Qwen model can offer broader edits after you choose to download it.
Try a real English correction example
Paste the original sentence into the editor and choose Quick check. This sentence is also part of LocuText's existing Harper regression cases.
Original
This is a example of bad grammer.
After accepting both suggestions
This is an
example of bad grammar.
| Change | Reason |
|---|---|
| Use an before the vowel sound at the start of example. | |
| Correct the spelling of the word. |
You can accept just one change and keep the other wording. This short example shows covered errors, not a promise to catch every tense, collocation, or contextual mistake.
Know the checking limits
- English dialect
- American English by default. There is currently no British, Canadian, or Australian English selector; review variant spellings yourself.
- Draft length
- Quick check supports up to 20,000 characters, not 20,000 English words.
- Input formats
- Type, paste, or import a TXT file. Direct Word and PDF imports are not supported.
- Style suggestions
- Off by default and available in Check settings. Wording preferences are not necessarily grammar errors.
If a name or technical term is flagged incorrectly, use Ignore spelling in this draft. It applies only to the current draft. Changing the interface language changes the controls, not your text or the English dialect.
Review each change
- Open the editor, then type, paste, or import a TXT draft.
- Choose Quick check and start a check of the current text.
- Review highlighted changes in the full-document diff, or preview the full draft before applying pending edits. Copy or export your result when done.
Local processing and offline use
The proofreading code does not upload your draft. Quick check downloads its runtime files with the app, then can work offline once those files are cached in the same browser. Drafts are not saved automatically, so copy or export your text before closing the page. Read the privacy and offline notice for details about downloads, browser storage, and hosting data.
Frequently asked questions
Do I need a local AI download to check English?
No. Harper quick check runs in your browser without Qwen or MacBERT. The first visit still needs to download the app and quick-check runtime files.
Model preparation is needed only if you choose Local AI. That mode currently supports up to 3,000 characters and 80 sentences per check and needs usable WebGPU. See the checking engine guide for model choices and limits.
What kinds of writing can I check?
Start with an English email, article draft, or mixed Chinese and English text, then review the suggestions in context. Technical terms, quotations, and facts still need your judgment; no suggestions does not mean a draft is error-free.
Can I accept only some suggestions?
Yes. Accept or reject each suggestion, or preview the final draft before applying the remaining edits. Batch actions do not apply rejected suggestions.
See the Chinese proofreading and local AI guide for Chinese checking options, long-draft review, and offline setup. The FAQ covers saving, browsers, and caches.
About the English checking engine
English quick checks use Harper's local linting interface, running in LocuText's browser Worker. Upstream capabilities and the features enabled here can differ; this page describes LocuText's current behavior.