What is the Online Proofreader?
This online proofreader runs a full editing pass over your text in one go: spelling, punctuation and spacing, sentence structure, and commonly confused words like their/there, its/it's and affect/effect. Paste a draft and every issue is listed with the sentence it appears in, a plain-English explanation, and a one-click fix where one is possible. Results are grouped into four categories with counts, so you can filter down to just spelling or just structure if that is all you want to focus on, or fix everything in one pass with "Fix all". It runs the same rule engine used by the Spell Checker and Sentence Checker, combined into a single check.
The one category unique to this page is "commonly confused words" — a set of context-aware checks for the classic English mix-ups that a plain spelling dictionary cannot catch, because both words are spelled correctly. "Their is a problem" and "There own decision" both use a real word in the wrong place; this proofreader looks at the word immediately before and after the flagged word to guess which one you meant, and flags it as a possible mix-up rather than a hard rule, since context-based guessing is never certain.
Why use a free online proofreader?
One pass, four categories
Spelling, punctuation, sentence structure and commonly confused words are checked together, so you get a complete pass instead of running four separate tools.
Filter down to what you care about
A segmented filter lets you view all findings or narrow to just one category — useful when you have already handled spelling and want to focus on structure.
Catches wording mix-ups spelling checkers miss
Their/there, its/it's, your/you're, affect/effect and similar pairs are all spelled correctly on their own — a dictionary spell check cannot catch them, but this proofreader's context rules can.
Fix all, or fix issue by issue
Apply every suggested correction across all four categories at once, or work through findings one at a time and skip the ones you disagree with.
No account, no upload
The whole check runs in your browser. Nothing you paste is sent to a server, which matters for drafts you are not ready to share.
How do you use the Online Proofreader?
- 1
Paste your draft
Works on anything from a paragraph to a full article. Checking updates automatically as you type, with a short debounce.
- 2
Read the category counts
Spelling, punctuation, structure and word-choice issues are each counted separately at the top, so you can see at a glance where the draft needs the most work.
- 3
Filter or scroll through findings
Use the category filter to focus on one issue type, or leave it on "All" to work through everything in reading order.
- 4
Apply fixes
Click a suggestion to apply it, or use "Fix all" to apply every available correction across all categories in one click.
- 5
Copy the cleaned-up text
Once findings are resolved, copy the corrected draft directly out of the tool.
What does it look like in practice?
A wording mix-up neither spelling nor structure checks catch
Input
Its a familliar story, and its one every agency recieves eventually.
Result
Spelling: "familliar" → "familiar", "recieves" → "receives". Wording: "Its a" → possible mix-up, did you mean "It's a"?
This single sentence trips three different categories at once — exactly the case a combined pass is built for. A spelling-only tool would miss the its/it's mix-up entirely, because "its" is a correctly spelled word.
A structure issue alongside a punctuation issue
Input
The report was due friday but the team kept finding new problems.Everyone was frustrated.
Result
Punctuation: missing space after "problems." · Structure: missing capital letter is not triggered here since "Everyone" is already capitalised.
The missing space between "problems." and "Everyone" is a punctuation-category find, independent of the spelling and structure checks running over the same sentence.
A clean sentence with nothing to flag
Input
The team shipped the feature on schedule and the client was pleased with the result.
Result
No issues found — this draft is clean by every check.
When nothing trips any of the four rule categories, the tool says so directly rather than showing an empty, ambiguous result.
How accurate is it?
Every finding across all four categories comes from the same deterministic rule engine used individually by the Spell Checker and Sentence Checker — dictionary lookups for spelling, regex pattern checks for punctuation and spacing, count-based thresholds for sentence structure, and context patterns for commonly confused words. Nothing here is probabilistic or AI-generated.
- The wording (commonly-confused-word) checks look at the word immediately next to the flagged term — "their is" flags as a likely mix-up, but a more distant or unusual sentence construction can slip past the pattern.
- Because four rule sets run together, a single sentence can trigger multiple findings from different categories — this is expected and shown as separate entries, not merged into one.
- This is a rule-based proofreader, not an AI grammar model. It cannot judge tone, argument quality or whether a sentence says what you actually meant — only mechanical spelling, punctuation, structure and known word-confusion patterns.
What should you know before using it?
What this tool is, where it runs and what it costs — the facts people usually check before trusting a free tool with their work.
| Detail | Online Proofreader |
|---|---|
| Category | Writing ToolsOne of 12 tools in this category. |
| Where it runs | Entirely in your browserYour input is never transmitted. Verify it yourself in the Network tab of your browser DevTools. |
| Price | FreeNo account, no trial, no usage cap, no paid tier. |
| Works offline | Yes, once the page has loaded |
| Also known as | free online proofreader, online proofreader online, online online proofreaderOther names people search for this by. |
Which tools relate to the online proofreader?
The online proofreader is one of 12 writing tools on this site. These are the ones most often used alongside it — either because they handle the next step in the same job, or because they answer a question this tool raises.
Spell Checker
The spelling category here is the exact same dictionary check, isolated on its own page for when that is all you need.
Sentence Checker
The structure category here is the exact same sentence-length and run-on check, isolated on its own page.
Punctuation Checker
The punctuation category here is the exact same spacing, bracket-balance and terminal-punctuation check, isolated on its own page.
Paragraph Rewriter
Once your draft is clean of mechanical errors, this tool offers optional clause-reordering and word-choice rewrites for style, rather than error-fixing.
When should you use a online proofreader?
Because the online proofreader runs entirely in your browser, it suits work you would not want to hand to a third-party server — client files, unpublished drafts, anything under an NDA. These are the situations people reach for it in most often.
Final pass before publishing
Run a complete article, email or report through once at the end of editing to catch mechanical issues across all four categories in a single check.
Reviewing a draft you did not write
When editing someone else's work, a category breakdown makes it easy to give specific, actionable feedback rather than a vague "needs a proofread" note.
Non-native English writing
The commonly-confused-word checks specifically target mix-ups (its/it's, their/there, affect/effect) that are common across all English writers, regardless of first language.
Cleaning up copy-pasted or merged documents
Documents assembled from multiple sources often pick up spacing and punctuation inconsistencies alongside genuine typos — a combined pass catches both at once.
Frequently asked questions
What does an online proofreader check that a spell checker does not?
How does it catch mix-ups like "their" vs "there"?
Is this an AI grammar checker?
Can I check just one category, like spelling only?
Does "Fix all" apply every suggestion at once?
Will it catch grammar mistakes that aren't spelling, punctuation or these specific word mix-ups?
Is my draft private?
Is the online proofreader safe to use?
This tool runs entirely inside your browser. Your text, files and settings are processed on your own device and are never uploaded to our servers — there is nothing for us to store, log or leak. You can confirm it yourself: open your browser DevTools, switch to the Network tab, and use the tool. You will not see an upload request. It also means the tool keeps working if your connection drops mid-task.
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