Does this tool check grammar properly?

It runs seven specific mechanical checks and says so. It is not a parser, so it will not catch tense errors, subject-verb agreement across long clauses or dangling modifiers. Read the published rule list before relying on a clean result.

Which specific checks does it run?

Repeated words, a and an agreement by sound, seven commonly confused word pairs in context, sentence capitalisation, paragraphs without terminal punctuation, and unmatched brackets and quotation marks.

Why does it flag phrases like had had or that that?

Because the repeated-word rule cannot tell a deliberate doubling from a typo. Both can be correct, so the finding carries a note saying it may be intentional; the rule reports it and leaves the decision with you.

Does it rewrite my text automatically?

No. It never edits the draft. Each finding suggests a corrected fragment in a separate column, which you can copy by hand, so nothing changes without your knowledge.

Will it find spelling mistakes?

No. There is no dictionary in the engine, so misspellings are out of scope. The confusion pairs cover a handful of words that spell-checkers handle badly, but a real spell check is a separate job.

Grammar Checker

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Issues by check

Start typing above — the results update as you write.

What is checked

These six checks run, and only these six: repeated words; a / an agreement; confusion pairs (your/you're, its/it's, then/than, to/too, loose/lose, affect/effect, weather/whether); sentence capitalisation; paragraphs without terminal punctuation; and unmatched brackets and quotation marks.

This is not a full grammar checker. It has no parser, so it cannot judge tense, agreement in complex clauses, dangling modifiers or word order. Choose a tool that states what it checks over one that claims everything.

This grammar checker publishes the exact list of rules it runs, so a clean result means "none of these checks fired" rather than an unqualified claim about your writing.

What is Grammar Checker?

A grammar checker is only as honest as the errors it claims to find, so this one publishes its rule list. Seven mechanical checks run and the page names every one of them. If none fires you see a clean result qualified as exactly that: none of these checks found anything, which is not the same as a guarantee that the text is correct.

The checks cover the common errors that survive a careful draft because the eye skips them. A repeated word — the the, is is — is caught wherever two identical words sit back to back. Article agreement is checked against sound rather than spelling, so a apple becomes an apple, a university stays a university, and an MRI is recognised as needing an because the letter M is read em. Seven confusion pairs are checked in context: your and you're, its and it's, then and than, to and too, loose and lose, affect and effect, and weather and whether. None is flagged on sight; each is flagged only in a construction where the wrong one has almost certainly been used, such as your going or more then enough.

The remaining checks are structural rather than lexical. A sentence that begins with a lowercase letter after a full stop is flagged, with abbreviations such as e.g. and single initials excluded so the rule does not misfire on ordinary academic prose. A paragraph that never ends with punctuation is flagged, because a missing full stop is easy to lose while editing a long document. Unmatched brackets, braces and quotation marks are reported with the count on each side, which is the fastest way to find a stray opening parenthesis.

Precision is the design goal, because a grammar check that cries wolf gets ignored. Every rule is written to fire on a clear error and stay silent on a correct sentence, which is why had had and that that are still reported but carry a note that they may be deliberate. A false positive costs trust, and trust is the entire value of a mechanical checker.

What the tool cannot do matters just as much as what it can. There is no parser behind it, so it cannot judge tense consistency, subject-verb agreement across a long clause, dangling modifiers, pronoun reference or word order. It will not find a misspelling, because it carries no dictionary, and it will not comment on style. Those tasks need either a much larger grammar model or a human reader, and a tool that implied otherwise would be doing you a disservice. Fix the mechanical findings, then read the text once more yourself.

Everything runs in the browser. Nothing is uploaded, stored or logged, and the text disappears when the tab closes, which makes the checker usable on drafts you would not paste into a web service. Copy report and Download produce a plain-text list of the findings you can keep beside the draft.

Use it as the last mechanical pass rather than the first. Draft freely, then run the checks before sending anything that has to be clean: a report, a submission, a covering email. Clearing the flagged items takes a minute and removes the small errors that make a reader doubt the larger ones. When the report comes back empty, that is the moment to read the piece aloud, because the mistakes that remain are the ones a script cannot see.

How to use Grammar Checker

Paste your draft; all seven checks run as you type and the count for each appears immediately.
Read the findings table from the top: each row names the check, the issue and a suggested fix.
Apply the mechanical fixes, starting with repeated words and the confusion pairs.
Re-read the paragraphs flagged for missing terminal punctuation, which are often still in progress.
When the report is empty, read the text aloud — the remaining mistakes are the ones no script can find.

When to use Grammar Checker vs related tools

Use this grammar check as the mechanical pass at the end of drafting, once the wording is settled. When the issue is sentence construction rather than a mechanical slip, the Sentence Complexity Analyzer finds the overloaded sentences, and the Passive Voice Detector covers a construction this checker deliberately ignores.

If the draft is clean but reads as heavy, the Readability Grade Scorer reports the reading level and the counts behind it, which is a different question from correctness.

Privacy & Security

This tool runs entirely in your browser — no data ever leaves your device. There is no server round-trip, no upload, no logging, and no account required. Your input is processed locally using client-side JavaScript and is never stored, transmitted, or accessible to anyone else. When you close the tab, everything disappears.