Grammar & Spelling Checker
Catch spelling, grammar, punctuation and wordiness as you type.
Mistakes
0
Worth checking
0
Suggestions
0
Reading ease
—
needs 10+ words
0 mistakes, 0 to check, 0 suggestions.
Paste something to check
Spelling, grammar, punctuation, clarity and concision, all checked in this tab. Nothing leaves your device.
What this tool can and cannot do. It matches patterns — misspellings, punctuation, agreement, wordy phrasing, passive voice. It does not parse sentences or understand meaning, so it will miss mistakes that need context, and some suggestions will not suit your sentence. Treat every suggestion as a prompt to look again, not an instruction.
Private by design. This tool runs entirely in your browser. Your input is processed on your own device and is not uploaded by DO101.
About the Grammar & Spelling Checker
Paste an essay or report and see spelling slips, punctuation errors, subject–verb disagreements, confusable words, wordy phrases and passive voice underlined in place. Every suggestion explains itself, and the clear-cut mistakes can be fixed in one click. It all runs in this tab — your work is never uploaded.
How to use it
- 1Paste or type your text into the editor.
- 2Underlines appear as you write: red for mistakes, orange for things to check, blue for suggestions.
- 3Click any underlined phrase to see why it was flagged and accept or ignore the fix.
- 4Use "Fix clear mistakes" for the unambiguous ones, then copy your text back out.
What you get
- Spelling, including the inflected forms of common misspellings
- Grammar: a/an, subject–verb agreement, double negatives, confusable words
- Punctuation: spacing, comma splices, repeated marks
- Clarity and concision: wordy phrases, nominalisations, filler, hedging
- Passive voice, overlong sentences and repeated words
- One-click fixes for the unambiguous errors only
- No word limit, no account, and nothing leaves your browser
Frequently asked questions
Is this really free?
Yes, with no account and no word limit. The checker is a rule engine that ships with the page, so running it costs nothing to serve — which is why there is nothing to charge for.
How does it compare to Grammarly?
Honestly: it catches less. Grammarly uses trained language models that understand sentence structure; this is a rule-based checker, so it finds mistakes that follow recognisable patterns and misses ones that need context. What it does give you is unlimited free checking, an explanation for every flag, and text that never leaves your device.
Is my essay uploaded anywhere?
No. There is no upload endpoint. The checking runs in JavaScript in your browser, and you can confirm that by opening your browser's network tab while you type.
Will it catch every mistake?
No, and no checker will. It cannot tell whether your argument holds, whether a citation is right, or whether you have used a real word in the wrong sense. Read your work aloud as well — it is still the best proofreading method there is.
Why is it flagging something that is correct?
Rules produce false positives, especially around passive voice and contractions, which are correct in plenty of writing. Every flag can be ignored, and whole categories can be switched off with the filter chips.
Keep going
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