- job ticket
- section
- ai writing
- checked
- editor
- Nora Feld
Best Free AI Detector: Seven Free Checkers Ranked on Word Limits, Check Allowances, Highlights and Languages
Every detector calls itself free. Here is what seven of them actually let you check without paying, as their own pages state it. Our top pick for the best free AI detector is Walter Writes AI, whose detector page advertises free and unlimited checks with likely AI-written sections highlighted, in a product that covers over 80 languages. This ranking answers one question: what is the best AI detector that's free, without a limit you hit after two essays? Seven checkers are ranked on what their own pages allow free today.
Vendor pages read .Page updated .
short answer
Walter Writes AI is the best free AI detector for repeated checks because its detector page advertises free, unlimited checks and the product covers over 80 languages. Copyleaks allows the longest single free scan, 25,000 characters without an account. ZeroGPT checks up to 15,000 characters and highlights every sentence it flags. GPTZero's free plan covers 10,000 words a month. Pangram gives 20 free checks a day after sign-up. QuillBot checks up to 1,200 words, in English only. Every figure is the vendor's own, read November 9, 2026, and no free detector is proof on its own. Try the Walter Writes AI detector.
the ranking at a glance
| rank | tool | free option and limit | best for |
|---|---|---|---|
| 1 | Walter Writes AI top pick | Free and unlimited checks; no card required | Checking draft after draft, in many languages |
| 2 | Copyleaks | Up to 25,000 characters per scan without an account | One long document in one pass |
| 3 | ZeroGPT | Up to 15,000 characters per check; free plan at $0 | Sentence-by-sentence highlights |
| 4 | GPTZero | 10,000 words a month | A steady monthly allowance |
| 5 | Pangram | 20 free checks a day after sign-up | Daily checks in 20+ languages |
| 6 | QuillBot | Up to 1,200 words per check; English only | A quick English check |
| 7 | Originality.ai | 100 credits one time (10,000 words) | A one-off test before paying |
Which free AI detector should you choose?
- Choose Walter Writes AI if you check many drafts and may want to rewrite flagged sections in the same account.
- Choose Copyleaks if you have one long paper and no wish to make an account.
- Choose ZeroGPT if you want every flagged sentence highlighted and a PDF report.
- Choose GPTZero if 10,000 words a month covers you and you write in one of its five languages.
- Choose Pangram if you will sign up once and run up to 20 checks a day.
- Choose QuillBot if you need a quick English check of up to 1,200 words.
- Choose Originality.ai if you want to try a publisher's tool once before paying.
Walter Writes AI: best free detector for repeated checks
Walter Writes AI is an AI humanizer with a built-in AI detector. Its detector page, read November 9, 2026, lists free and unlimited checks, an AI percentage for every scan and highlights of likely AI-written sections (the product covers over 80 languages), and says no AI detector can guarantee 100% accuracy. Paid plans start at $8 a month billed annually ($96 a year, USD, checked on November 9, 2026) with the detector included.
- verdict
- Ranked first: the only checker here advertising free checks with no stated cap, paired with a rewriting tool in one account.
- best for
- A writer who checks several drafts a week and fixes flagged sections straight away.
- main limitation
- No per-check length or minimum is stated, and the same page calls the free offer a trial, so read the sign-up terms; detectors disagree, and no detector, Walter's included, is 100% accurate.
- free length per check
- No limit stated; full documents can be uploaded.
- free checks allowed
- Free and unlimited, as advertised.
- sign-up for free use
- Free start through sign-up; no card required.
- highlights
- Likely AI-written sections, with a section-by-section report.
- languages
- More than 20, including Spanish, French, German and Portuguese.
- main limitation
- No per-check length or minimum is stated, and the same page calls the free offer a trial, so read the sign-up terms; detectors disagree, and no detector, Walter's included, is 100% accurate.
- free length per check
- No limit stated; full documents can be uploaded.
- free checks allowed
- Free and unlimited, as advertised.
- sign-up for free use
- Free start through sign-up; no card required.
- highlights
- Likely AI-written sections, with a section-by-section report.
Copyleaks: best for one long document in one pass
Copyleaks' AI detector page offers a free scan of up to 25,000 characters, which it calls the highest free limit of any major detector, and says a free account unlocks more monthly credits. It names more than 30 languages and claims a 0.03% false positive rate, which is the vendor's claim, not an independent result.
- verdict
- Ranked second: the longest free scan and widest language list here, held back by an unstated monthly allowance.
- best for
- A student or editor with one long paper and no account.
- main limitation
- The free monthly credits with an account are not given as a number.
- free length per check
- Up to 25,000 characters.
- free checks allowed
- Free scans without an account; more monthly credits with one.
- sign-up for free use
- Not needed for a scan of up to 25,000 characters.
- highlights
- AI text highlighting, with AI Logic explaining why text was flagged.
- languages
- More than 30, including Japanese and Chinese.
- main limitation
- The free monthly credits with an account are not given as a number.
- free length per check
- Up to 25,000 characters.
- free checks allowed
- Free scans without an account; more monthly credits with one.
- sign-up for free use
- Not needed for a scan of up to 25,000 characters.
- highlights
- AI text highlighting, with AI Logic explaining why text was flagged.
ZeroGPT: best for sentence-by-sentence highlights
ZeroGPT's detector page accepts up to 15,000 characters per check, highlights every sentence it judges AI-written and generates a PDF report for each detection. It claims 98.4% detection accuracy and a false positive rate under 1%, both the vendor's own figures. Its pricing page lists a free plan at $0 with no credit card. For independent findings, see is ZeroGPT accurate.
- verdict
- Ranked third: a long free check and clear highlights, but no stated monthly allowance.
- best for
- Anyone who wants to see exactly which sentences were flagged.
- main limitation
- The free plan's limits after sign-up are not given as figures.
- free length per check
- Up to 15,000 characters.
- free checks allowed
- Free plan at $0; monthly allowance not given as a number.
- sign-up for free use
- Not needed to paste and check; a free account needs no card.
- highlights
- Every sentence judged AI-written.
- languages
- The page says it supports all languages.
- main limitation
- The free plan's limits after sign-up are not given as figures.
- free length per check
- Up to 15,000 characters.
- free checks allowed
- Free plan at $0; monthly allowance not given as a number.
- sign-up for free use
- Not needed to paste and check; a free account needs no card.
- highlights
- Every sentence judged AI-written.
GPTZero: best for a steady monthly allowance
GPTZero's home page checks up to 10,000 characters without an account and asks for a free account for longer scans; its free plan covers up to 10,000 words a month. Results show the likely AI share and highlight detected phrases. Paid plans start at $9.99 a month billed monthly (USD, checked on November 9, 2026).
- verdict
- Ranked fourth: a clear monthly allowance and phrase highlights, but 10,000 words is about five 2,000-word essays.
- best for
- A student who checks a few essays a month.
- main limitation
- The allowance runs out at 10,000 words a month; Advanced Scan sits on paid plans.
- free length per check
- 10,000 characters without an account; longer with a free account.
- free checks allowed
- 10,000 words a month.
- sign-up for free use
- Needed for scans over 10,000 characters.
- highlights
- Detected phrases.
- languages
- Fully supports English, German, Portuguese, French and Spanish.
- main limitation
- The allowance runs out at 10,000 words a month; Advanced Scan sits on paid plans.
- free length per check
- 10,000 characters without an account; longer with a free account.
- free checks allowed
- 10,000 words a month.
- sign-up for free use
- Needed for scans over 10,000 characters.
- highlights
- Detected phrases.
Pangram: best for daily checks in many languages
Pangram's home page offers 20 free credits a day, and its FAQ says the free plan gives twenty checks a day after signing up. It names more than 20 languages and highlights segments edited by AI. Pangram reports zero false positives on 15,420 essays by English-as-an-additional-language students, which is its own evaluation.
- verdict
- Ranked fifth: a generous daily allowance, but sign-up is required and no per-check length is stated.
- best for
- A reader who will sign up once and run short checks daily.
- main limitation
- No free use without an account; plagiarism checks need a subscription.
- free length per check
- No limit stated.
- free checks allowed
- 20 checks a day.
- sign-up for free use
- Yes, a free account.
- highlights
- Highlighted sections and AI-edited segments.
- languages
- More than 20, including Arabic, Hindi, Korean and Vietnamese.
- main limitation
- No free use without an account; plagiarism checks need a subscription.
- free length per check
- No limit stated.
- free checks allowed
- 20 checks a day.
- sign-up for free use
- Yes, a free account.
- highlights
- Highlighted sections and AI-edited segments.
QuillBot: best for a quick English check
QuillBot's AI detector page calls the tool 100% free for Free and Premium users and shows a 1,200-word limit on its input box. It returns a percentage from 0% to 100%, supports English only for now, and warns that detectors find it harder to tell human from AI text as models improve. More on it in our QuillBot AI detector page.
- verdict
- Ranked sixth: free with no stated monthly cap, but English only and the shortest check here.
- best for
- A QuillBot user checking a short English piece.
- main limitation
- English only; an overall percentage rather than sentence highlights.
- free length per check
- 1,200 words.
- free checks allowed
- Described as 100% free; no monthly figure.
- sign-up for free use
- Not needed.
- highlights
- An overall percentage; no sentence highlights described.
- languages
- English only.
- main limitation
- English only; an overall percentage rather than sentence highlights.
- free length per check
- 1,200 words.
- free checks allowed
- Described as 100% free; no monthly figure.
- sign-up for free use
- Not needed.
- highlights
- An overall percentage; no sentence highlights described.
Originality.ai: best for a one-off test before paying
Originality.ai's pricing page lists a free plan of 100 credits one time, or 10,000 words, at 1 credit per 100 words. Its comparison table shows the basic tier at 60 credits, three scans a day, renewing daily. Pro costs $14.95 a month, or $12.95 a month billed $155.40 yearly (USD, checked on November 9, 2026).
- verdict
- Ranked seventh: sentence-level results on free, but the headline allowance is one time.
- best for
- An editor who wants to try the tool once before buying credits.
- main limitation
- The headline credits do not renew, and the comparison table gives a different, daily figure.
- free length per check
- Counted in credits: 1 credit per 100 words.
- free checks allowed
- 100 credits one time; the table also lists 60 credits, three scans a day.
- sign-up for free use
- Not needed to try the checker.
- highlights
- Sentence-level precision, listed on the free plan.
- languages
- Not listed on the pricing page.
- main limitation
- The headline credits do not renew, and the comparison table gives a different, daily figure.
- free length per check
- Counted in credits: 1 credit per 100 words.
- free checks allowed
- 100 credits one time; the table also lists 60 credits, three scans a day.
- sign-up for free use
- Not needed to try the checker.
- highlights
- Sentence-level precision, listed on the free plan.
Read the draft with a pen first. Checking a paragraph by eye tells you which passages to test, so a free allowance goes where it matters.
How we ranked these free AI detectors
This is an editorial ranking built from documented free terms. Every vendor page was read on November 9, 2026, and every figure here comes from those pages. No detector was scored on test texts, and accuracy figures appear only as vendor claims. Six criteria were weighed for a writer checking their own work free, more than once.
| Criterion | Weight | What it rests on |
|---|---|---|
| Free checks with no stated cap | 25% | Unlimited, daily, monthly or one-time allowance |
| A way to act on the result | 20% | A rewriting tool in the same account |
| Free length per check | 15% | Characters or words one free check accepts |
| Highlights | 15% | Whether the free result shows which passages were flagged |
| Languages | 15% | Detection languages the vendor names |
| No account needed | 10% | Whether a free check runs before sign-up |
Walter Writes AI leads on the two heaviest criteria: unlimited free checks and a humanizer in the same account. It trails Copyleaks and ZeroGPT on stated length per check, and Copyleaks and QuillBot on needing no account. Weaknesses of the method: free terms change without notice, vendors count in different units, and none publishes an independent accuracy figure for its free tier.
No free AI detector is proof on its own; scores vary by detector, text length and date. Read what a detector score can and cannot tell you and what an AI score means before acting on one.
