Spell Checker: catch what your browser misses
Five checking layers your browser doesn't have
Your browser already underlines words that are not in its dictionary, and this page keeps that working in the editor. What browsers cannot do is notice when a correctly spelled word is the wrong word: loose for lose, their for there, should of for should have. This checker adds five deterministic layers on top of the dictionary: a corpus of classic typos with their corrections, context rules that catch real-word errors, a Canadian and American spelling converter that works in both directions, doubled-word detection, and capitalization checks, each with one-click fixes. Every rule is a published pattern, not a guess, and everything runs in your browser: no account, no upload, no text sent to anyone's server, which is more than the famous grammar tools can say.
Why does spell check miss some mistakes?
Because standard spell check only asks one question: is this word in the dictionary? A typo that lands on a real word passes the test, so "I will loose my keys" and "their is a problem" sail through even though both are wrong; these are called real-word errors, and studies of writing errors consistently find they make up a large share of the mistakes that survive into finished documents. Catching them requires looking at context, not letters, which is exactly what the context layer above does with targeted rules like loose before weight, their before is, and to before much.
The real-word errors section shows the most common cases with the rules that catch them.
How to use the spell checker
Paste your text and pick a dialect
Choose Canadian or American English in the toolbar; the dialect layer flags spellings from the other side, like color in a Canadian document or colour in an American one, and the rest of the layers work the same either way.
Read the issues panel
Every finding appears on the right, colour-coded by layer: red for typos and doubled words, amber for context and capitalization, blue for dialect. Each card shows the word, the suggestion, and the surrounding text so you can judge it in place.
Fix one by one, or all at once
Each card's Fix button applies its single correction, preserving capitalization. Fix everything fixable applies all unambiguous corrections in one pass; review-level findings, where judgment is needed, are never auto-applied.
Let the browser handle the long tail
Rare words and names are the browser dictionary's job, and its squiggles stay active in the editor. The two systems are complementary: the dictionary knows more words; this checker knows more mistakes.
Copy or download the result
Copy text puts the corrected version on your clipboard and Download saves a .txt file. Nothing is stored or transmitted: close the tab and the text is gone.
Real-word errors: correctly spelled, still wrong
A real-word error is a mistake that produces a legitimate dictionary word, which makes it invisible to ordinary spell check. The checker's context layer targets the highest-frequency cases with precise rules: it looks at neighbouring words, so it flags "loose weight" without bothering the perfectly correct "loose thread". The layer diagram shows how the systems stack.
The browser dictionary remains the base layer with the most words; each added layer catches a class of error the layer below it cannot see. Review-level findings are flagged with guidance instead of auto-fixed.
| You typed | Rule suggests | Why |
|---|---|---|
| should of / could of / would of / must of | should have, could have… | "Of" after these verbs is always the sound of "'ve" written out; there is no correct reading. |
| their is / their are | there is / there are | Existence uses "there"; "their" only ever shows possession. |
| to much / to many | too much / too many | Degree takes "too" with two o's; "to" is the direction word. |
| loose weight / loose money / loose track | lose weight, lose money… | "Loose" means not tight; misplacing something is "lose", one o. |
| more … then / better … then | more … than | Comparisons take "than"; "then" is about time and sequence. |
| your welcome | you're welcome | It is the contraction of "you are welcome", not a welcome you own. |
| could care less | couldn't care less (review) | The idiom means caring is already at zero; flagged for review since the casual form is widespread. |
| irregardless | regardless (review) | Disputed rather than wrong; most style guides recommend "regardless". |
Canadian vs American spelling, both directions
Canadian English keeps British -our and -re endings and doubled L's while using American -ize verbs, a mix no other dialect shares. The dialect layer holds roughly 60 word families with their inflections and converts whichever way you choose: writing for a Canadian audience, it flags color, center, and traveling; writing for an American one, it flags colour, centre, and travelling. Words where context decides, like meter the device versus metre the unit, or licence the noun versus license the verb, are flagged for review with the rule attached rather than auto-changed.
| Pattern | Canadian | American | Auto-fixable? |
|---|---|---|---|
| -our endings | colour, honour, favour, neighbour, behaviour, labour, harbour, rumour | color, honor, favor, neighbor, behavior, labor, harbor, rumor | Yes, both directions |
| -re endings | centre, metre, litre, fibre, theatre, calibre, sombre | center, meter, liter, fiber, theater, caliber, somber | Yes, except "meter" in Canadian mode (devices are meters) |
| -ce / -se | defence, offence, pretence; licence (noun), practise (verb) | defense, offense, pretense; license, practice | -ce words yes; licence and practise flagged for review (part of speech decides) |
| Doubled L | travelling, cancelled, labelled, modelling, counselling, jewellery | traveling, canceled, labeled, modeling, counseling, jewelry | Yes, both directions |
| Other | grey, cheque, catalogue, moustache, pyjamas, sceptical, mould, sulphur, enrolment | gray, check, catalog, mustache, pajamas, skeptical, mold, sulfur, enrollment | Mostly yes; "cheque" only converts toward American (every cheque is a check, not vice versa) |
| Already shared | organize, realize, analyze, program, aluminum: Canadian uses these American-looking forms | Never flagged | |
The five ways fingers misspell
Classic misspellings are not random: almost all of them fall into five mechanical patterns, and the typo layer's corpus of roughly 130 corrections is organized around them. Knowing the patterns makes you a better self-editor, because you know where to look.
| Common misspelling | Correct | Pattern |
|---|---|---|
| definately | definitely | Sound-alike vowel |
| recieve | receive | ie / ei swap |
| seperate | separate | Sound-alike vowel |
| occured | occurred | Missing doubled letter |
| untill | until | Extra doubled letter |
| teh | the | Transposition |
| goverment | government | Dropped letter |
| accomodate | accommodate | Missing doubled letter |
| embarass | embarrass | Missing doubled letter |
| wierd | weird | ie / ei swap (an exception word) |
| alot | a lot | Fused words |
| tommorow | tomorrow | Doubled the wrong letter |
Commonly confused words, with the deciding question
Homophones and near-homophones cause most real-word errors, and each pair has a one-question test that settles it. The scanner flags the patterns it can judge safely; this table is the reference for the rest, the cases where only you know what you meant.
| Pair | The deciding question | Scanner |
|---|---|---|
| their / there / they're | Possession? "their". A place or "there is"? "there". Can you say "they are"? "they're". | Assisted |
| your / you're | Can you say "you are"? Then "you're". Otherwise it is possession: "your". | Assisted |
| its / it's | Can you say "it is" or "it has"? Then "it's". The possessive "its" never takes an apostrophe. | Reference |
| lose / loose | Misplacing or failing? "lose", one o. Not tight? "loose". | Assisted |
| than / then | Comparing? "than". Time or sequence? "then". | Assisted |
| affect / effect | Usually: "affect" is the verb (to influence), "effect" is the noun (the result). | Reference |
| to / too | "Too" means also or excessively; everything directional is "to". | Assisted |
| accept / except | Receiving or agreeing? "accept". Excluding? "except". | Reference |
| advice / advise | "Advice" is the noun you give; "advise" is the verb you do. The s sounds like z. | Reference |
| complement / compliment | Completes something? "complement". Says something nice? "compliment". | Reference |
| principal / principle | A person or "main"? "principal". A rule or truth? "principle". | Reference |
| stationary / stationery | Not moving? "stationary". Paper and envelopes? "stationery", e for envelope. | Reference |
What most spell checkers leave out
| Capability | Typical online checker | This checker |
|---|---|---|
| Real-word error rules | Dictionary lookup only | Context rules: should of, their is, loose weight, to much, and more |
| Canadian English support | US-only, flags colour as wrong | Canadian or American target, converter both directions |
| Part-of-speech traps | Auto-changes licence and practise | Flagged for review with the rule attached, never auto-applied |
| Doubled-word detection | Sometimes | Always, with one-click removal |
| Explains its findings | Suggestion without a reason | Every card shows the pattern and the context |
| Privacy | Text uploaded to servers for analysis | Fully client-side; nothing transmitted, works offline |
| Accounts and limits | Word caps, signup walls, premium tiers | Free, no account, no length limit |
| Works with browser spell check | Replaces it | Complements it: the dictionary stays active in the editor |
One checker, four kinds of writing
Essays in proper Canadian English
Canadian assignments expect Canadian spelling, and autocorrect trained on US English quietly sabotages that. Set the dialect to Canadian, paste the draft, and bring every color and center home before submission, with the typo and context layers catching what proofreading at 2 a.m. does not.
Emails and documents that read clean
A "should of" in a client email costs more credibility than it should. The context layer exists for exactly these reflex errors, and because everything runs locally, confidential text never leaves the machine, which makes this usable where cloud grammar tools are banned.
The pairs that dictionaries can't teach
Their, there, and they're all pass spell check, which makes them the hardest errors for second-language writers to self-catch. The scanner flags the risky patterns, every card explains its reasoning, and the confusables table carries the deciding questions for the rest.
A mechanical pass before the human one
Run the mechanical errors out first: doubled words from edits, fused alots, transposed teh's, dialect drift from pasted research. What remains is the real editing, and the corpus-based layer means the fixes applied are exactly the ones no editor would debate.
Six proofreading mistakes
Trusting the squiggles completely
No squiggle does not mean no error: real-word mistakes pass every dictionary on earth, and they are the errors that make it to print.
Treat the dictionary as layer one. Run a context-aware pass, then read the text aloud once.Letting US autocorrect write Canadian
Phone and laptop autocorrect default to US English and will un-Canadianize a document one colour at a time without telling you.
Set your devices to Canadian English where possible, and run the dialect layer before anything official goes out.Accepting every suggestion blindly
Auto-fix is safe only when the correction is unambiguous; licence versus license depends on part of speech, and no machine should decide that silently.
Apply the one-click fixes, but read the review-level cards; they are flagged instead of fixed for a reason.Proofreading only on screen
Your brain autocorrects your own writing as you read it, which is why doubled words survive a dozen readings.
Change the presentation: a different font, printed paper, or reading aloud breaks the autocorrect in your head.Fixing spelling but not consistency
Colour in one paragraph and color in the next is more visible to a reader than either spelling alone, and both pass a US-or-UK-agnostic checker.
Pick a dialect per document and enforce it; that is what the converter's one-click pass is for.Pasting confidential text into cloud tools
Most online checkers send your text to a server for analysis, which can violate workplace policy before it improves a single sentence.
Check sensitive text with tools that run locally. This page works with the network cable unplugged.Spelling terms, defined
- Real-word error
- A mistake that produces a legitimate dictionary word, like loose for lose or their for there, invisible to dictionary-based spell check and catchable only from context.
- Homophone
- Words that sound alike but differ in spelling and meaning: their, there, and they're. The fuel of real-word errors.
- Transposition
- Two letters swapped by fast fingers: teh for the, taht for that. The most mechanical typo type and the easiest to auto-correct.
- Dialect spelling
- Systematic national differences like colour and color or centre and center. Neither is wrong; documents are wrong only when they mix them.
- Canadian Oxford preference
- The spelling choices of the Canadian Oxford Dictionary, the conventional reference for Canadian English: -our, -re, doubled L, and American -ize together.
- Review-level finding
- A flag the checker raises but refuses to auto-fix because the correction depends on meaning or part of speech, like licence versus license.
- Doubled word
- The same word twice in a row, usually a editing artifact: "the the". Famously resistant to human proofreading because the brain reads past it.
- Autocorrect drift
- Gradual dialect contamination from device autocorrect trained on a different English than the one you are writing.