These two get shortlisted together constantly, and they should not be. They are built for different buyers, they price on different units, and — the part nobody mentions in comparison posts — only one of them will show you what it costs without a conversation. This page compares what each vendor actually publishes, checked on 16 August 2026, and is explicit about the places where the answer is "they do not say".
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Winston AI sells credits on a published, self-serve ladder. You can read the price, pick a tier and start, and the number of words you can scan per month is printed on the page.
Copyleaks sells to institutions — universities, publishers, enterprises — and its buying process reflects that. It is a plagiarism-and-AI suite with an established footprint in education, not a paste-box you sign up for on a Tuesday afternoon.
If you are one person who wants to check drafts, Winston's ladder is the one you can actually act on today. If you are procuring for a university or a compliance function, Copyleaks is on the shortlist for reasons that have little to do with the detector itself. Most people searching this comparison are the first kind of buyer and do not realise they are reading about the second.
Taken from gowinston.ai/pricing on 16 August 2026. Winston shows monthly and annual columns side by side and advertises the annual route as a 45% saving.
| Tier | Monthly | Billed annually | Credits |
|---|---|---|---|
| Free | $0 | $0 | 2,000 credits, 14-day trial |
| Essential | $18/mo | $10/mo ($120/yr) | 100,000 credits/month |
| Advanced | $29/mo | $16/mo ($192/yr) | 200,000 credits/month |
| Elite | $49/mo | $26/mo ($312/yr) | 500,000 credits/month |
Three things in that table are worth more than the headline price.
The free tier is a trial, not a floor. It is 2,000 credits across 14 days. That is enough to evaluate Winston and not enough to use it, which is a legitimate design choice but a different thing from an ongoing free allowance you can return to next month.
Team size is a tier gate, not an add-on. Advanced lists up to 5 team members; Elite lists unlimited. So on Winston the question "how many of us need this" moves you up the ladder rather than adding a line to the invoice, and credits pool across subscribed team members rather than being allocated per person.
Credits are the unit, and top-ups exist. A credit-metered plan is cheap when volume is low and rises exactly on the month you are busiest. Whether that is good or bad depends entirely on whether your volume is predictable.
We tried to check, twice, a day apart. On both 15 and 16 August 2026 requests to Copyleaks' pricing page from our tooling were refused with an HTTP 403 by its bot protection, as were its homepage, its AI content detector page and its sitemap.
That is not a criticism and it does not mean the site is down — plenty of companies filter automated traffic, and Copyleaks' pricing loads normally in an ordinary browser. But it does mean we cannot quote a Copyleaks figure and stand behind it, so we will not quote one at all. Read Copyleaks' pricing on Copyleaks' own site before you buy anything, and treat any third-party page that prints a confident Copyleaks price — including the ones that rank above this one — as a number somebody may have copied from a post written two years ago.
What can be said without a price is what the product is aimed at. Copyleaks pairs AI detection with plagiarism detection in one platform, and its centre of gravity is institutional: LMS integrations, organisation-wide deployment, the procurement and compliance surface that a university or an enterprise publisher needs. That is a genuinely different product from a per-seat writing tool, and the reason it appears on shortlists next to Winston is mostly that both words appear in the same search results, not that they solve the same problem.
This is where the comparison gets uncomfortable for everyone, us included.
Winston's AI content detector page, read on 16 August 2026, describes the product as "The Most Accurate AI Detector", claims "best-in-class accuracy", "unmatched accuracy in AI detection", and says the detector is "tuned to eliminate false positives". Those are the vendor's words. What that page does not carry is a number — no accuracy percentage, no false-positive rate, no linked evaluation you can check the claim against.
Copyleaks' materials were not reachable to us for the reason above, so we cannot characterise what it publishes today.
Our own position, since we sell a detector too: no AI detector on the market — ours included — should be treated as proof. Every English-language detector in this category, ours built on DeBERTa, RoBERTa and ELECTRA, produces false positives, and they fall disproportionately on writers whose first language is not English. Any vendor telling you otherwise is selling you certainty that does not exist. The useful question is not "which one is right" but "which one shows me *why* it flagged something", because a sentence-level highlight is something you can argue with and a single percentage is not.
How to test either of them properly. Take five pieces of your own writing that you know are human, and five you know are machine-written, in the domain you actually work in. Run all ten. Count the false positives. That fifteen-minute exercise tells you more than every accuracy claim published by every vendor in this comparison, including this one.
Strip away the marketing and the two vendors are asking you a different question.
Winston asks how many words. That suits someone with steady volume who can estimate a month ahead, and punishes someone whose workload spikes — the busy month is the expensive month, and top-ups are how the gap gets filled.
Copyleaks asks, in effect, how big is your organisation. That suits a procurement process with a budget line and a security review, and is heavy machinery for one person checking blog drafts.
Neither model is wrong. But notice that neither is a flat price for a person who writes. That is the gap most people in this comparison actually fall into, and it is why a third answer belongs on this page.
TextSight prices flat, per tier, with no credit meter:
The AI rewriter is bundled into the paid tiers rather than sold beside them, which matters because finding a flagged paragraph and fixing it is one job, and paying two subscriptions to do it is the most common way this budget quietly doubles.
We will be straight about where we are not the answer. We do not do plagiarism detection, so if what you need is originality-against-a-corpus rather than AI detection, Copyleaks is a category we are not in. And if you genuinely have unpredictable, very high volume, a credit meter can work out cheaper than a flat tier — run your own numbers rather than taking ours.
1. Write down your real monthly volume. Not your ambition — last month's actual word count. Credit pricing is only cheap if this number is small and stable. 2. Count the people who need a login. One person: any of the three. Two to five: check the tier that gates team members, because on Winston that is a jump up the ladder. More than five, with a compliance requirement: you are in institutional territory and Copyleaks belongs on the list. 3. Ask whether you need plagiarism detection. If yes, that narrows the field immediately and mostly settles it. 4. Run the ten-document test above on every finalist. Free tiers exist for this. Winston's is 14 days, so start the clock deliberately rather than by accident. 5. Check whether the fix is included. Detection tells you there is a problem. Something still has to solve it.
Every figure on this page was read from the vendor's own site on the date stated, not from secondary coverage.
Vendor pricing changes without notice. If you are reading this months later, check the dates above and verify anything you are about to spend money on.
The deeper head-to-head: feature table, where GPTZero wins, where TextSight wins, and migration steps.
Read the comparePerplexity, burstiness, and transformer scoring explained, so you can read any detector's verdict critically.
Read the guideWhy detectors over-flag ESL and formal writing, and how sentence-level evidence helps you defend real work.
Read the guideThe full ranking with detection approach, pricing, and use-case fit side by side.
See the rankingStart with TextSight's free tier. No card, no signup, no commitment. Your first scan in about six seconds, with the evidence shown line by line.
Honest comparisons vs other tools.