Five free checks a day. Pro when you need more.
5 checks a day stay free without an account. Pro raises the cap to 100. The HTTP API is a separate paid-key product — not a free tier.
- 5 successful checks per day
- 10–1,200 words per check
- Sentence-level pattern signals and cues
- No signup, no account, no card
- Submitted text is never stored
- Failed checks never count against you
Pro
100 / dayBilled $69/year
- 100 successful checks per day
- Same sentence-level method and method label
- Priority inference queue
- Cancel any time from the Stripe receipt
- Text is still never stored
- Not a detector bypass and not authorship proof
Checkout runs on Stripe. No draft text is ever sent to billing, and Pro does not change how your text is analysed. Operated by MentalCraft LLC.
API keys
Programmatic detection at POST /api/v1/detect returns per-sentence evidence arrays and
monthly word quotas. Paid keys only — there is no free API tier.
API Starter
50,000 words / month
- 50,000 API words per month for small tools and solo review workflows.
- Bearer key, sha256-stored, rotatable
- Monthly usage in every response
API Pro
300,000 words / month
- 300,000 API words per month for production writing tools and review queues.
- Bearer key, sha256-stored, rotatable
- Monthly usage in every response
Keys and usage live at /account/api. Limits and error semantics: quotas and the API reference.
Before you pay
Do I need Pro to use the detector?
No. The website includes 5 free checks per day with no account and no card. Pro only raises the daily cap to 100 checks.
What exactly does $9/month buy?
A higher daily allowance (100 checks instead of 5) and priority queueing. The detection method, the sentence-level output, and the privacy guarantee are identical on Free and Pro.
Can I cancel, and how?
Yes. Cancel any time from the Stripe receipt or the billing portal link in your receipt email. Access continues to the end of the paid period.
Does Pro make my text pass AI detectors?
No. Pro does not alter your text and we make no bypass or score guarantee. Pro is more checks per day, nothing else.
Is my draft sent to my payment provider?
No. Checkout never includes draft text. Payment handles billing details only, and detection drafts are never stored.
Is there a free API tier?
No. The HTTP API is paid keys only. The free allowance applies to the website, not the API.
What this is not
Pro does not prove authorship, raise a detector pass rate, or bypass Turnitin, GPTZero, Copyleaks, or any other checker. Results stay probabilistic review cues.