← Mephistopheles
Pricing
Start free. Pay when you need more.
Every plan runs the same grounded verification engine. Your allowance is how much
text it checks per day — across the extension, verified chat, and document checking.
Free
$0
25 KB/day
- ~170 checks or ~8 pages a day
- Extension, paste-to-verify & documents
- Sign in required
Start freeMost popular
Plus
$12/mo
1 MB/day
- ~40× the free allowance
- Bring your own model (your key) to chat + verify
- Document checking
Sign in to upgradePro
$59/mo
5 MB/day
- Heavy daily document review
- Everything in Plus
- Priority support
Sign in to upgradeEnterprise
Custom
Custom
- SSO, higher caps, SLA
- BYO at scale
Contact usNeed more than your plan on a busy day? Top up
any time — prepaid credit that never expires, used automatically once the day's allowance is spent.
Prices in USD. Cancel anytime.