Grammar Checker
Use this free online Grammar Checker to catch spelling slips, grammar errors and common style issues in any English text in seconds. It is useful for students proofreading essays, professionals tightening business emails, ESL learners building confidence, bloggers polishing posts before publishing, and anyone who would rather not paste a draft into yet another sign-up form. Paste your text into the box and click Check — issues appear inline with explanations and suggested replacements. There is no character limit, no account required, and nothing is uploaded to a server. Use the suggestions as guidance, then make the final call yourself before saving the cleaned-up copy.
What This Checks
The built-in checker looks for common mistakes such as double words, frequently misused homophones (their/there/they're, your/you're, its/it's), missing capitalization at sentence starts, double spaces, missing space after punctuation, and several common typos. For deeper checks, consider integrating a service like LanguageTool or Grammarly via API.
How to Use This Grammar Checker
Checking grammar is a two-step paste-and-click.
- Paste or type your text into the input area.
- Click Check Grammar to scan the text.
- Review the highlighted issues — each shows the problematic phrase, the explanation and a suggested fix.
- Accept or ignore each suggestion — you stay in control of the final wording.
- Click Copy to grab the corrected text for your document.
How This Grammar Checker Works
The grammar checker runs a layered set of rules over your text in your browser. The first pass catches plain spelling errors by checking each token against an English dictionary; words flagged as unknown are offered the most likely replacements based on edit distance. The second pass applies grammar rules — subject-verb agreement, article usage (a/an), apostrophe placement, double negatives, run-on sentences and the most common confusables (their/there/they're, your/you're, its/it's). The third pass flags style issues — passive voice, very long sentences, repeated words and weak hedging adverbs ('really', 'very', 'just'). Because the checker runs locally rather than calling a third-party API, your draft stays private and there is no character limit; the trade-off is that it cannot match the depth of a paid service like Grammarly Premium. Treat the suggestions as helpful prompts rather than absolute corrections — language is contextual and the tool occasionally flags valid phrasing in technical writing, dialogue, or creative work. Run the tool, accept the obvious wins, ignore the rest.
Last updated: May 2026.
Frequently Asked Questions
What does this checker miss?
Anything requiring grammatical context — agreement, tense consistency, ambiguous pronouns, run-on sentences, or stylistic problems. It's a first-pass screen, not a substitute for proofreading.
Does it work for languages other than English?
No, the rule set is English-only. For multilingual checking use a service like LanguageTool which supports 30+ languages.
Is "i" really always capitalised?
When used as the singular first-person pronoun, yes. When it's a math variable or part of an acronym lowercase is fine — the checker can't distinguish so review flagged "i" cases manually.
Why is the highlighted text different from my input?
Issues are wrapped in <mark> tags so you can see them in context. The underlying text is unchanged — copy it back from the highlighted view if needed.
Can I trust the checker for important documents?
Use it as a quick sanity check, but always proofread important documents yourself or have a second person review them. Automated checkers will miss errors a human reader would catch.