Stop bots and abuse without handing your visitors' data to Big Tech. Sentinel pairs a server-verified proof-of-work captcha with the deepest self-owned IP-reputation engine — geo, ASN, datacenter, VPN, Tor and abuse intelligence, all under your control.
Every signal is computed on infrastructure you own. No third-party trackers, no data sales, no surprises.
No fingerprinting, no cross-site tracking, and we never sell or share visitor data. Only coarse, non-PII signals are collected.
The browser solves a SHA-256 challenge; the hash is recomputed and verified server-side. The work is real and cannot be faked.
Challenge difficulty scales with the visitor's live risk band — clean traffic glides through, risky traffic works harder.
Pointer entropy, automation tells and headless signals feed a bot-likelihood score that flags or blocks automation.
Country, ASN and ASN org plus datacenter, VPN, Tor, proxy and abuse classification — built from data we own, not rented.
Your reputation lookups stay yours. Sentinel is self-hosted by design, so your security posture is never someone else's product.
The big providers verify humans. Sentinel verifies humans and tells you exactly who is connecting — without selling the answer.
| Capability | Sentinel | Google reCAPTCHA | Cloudflare Turnstile |
|---|---|---|---|
| Privacy-first (no tracking / no data sales) | Yes | No | Partial |
| Self-hosted / self-owned data | Yes | No | No |
| Server-verified proof-of-work | Yes | No | Partial |
| Adaptive, risk-based difficulty | Yes | Partial | Partial |
| Built-in IP-reputation depth (ASN, VPN, Tor, abuse) | Deep | No | Basic |
| Datacenter / proxy / Tor classification | Yes | No | Partial |
| Queryable reputation API | Yes | No | No |
Three steps to bot-resistant, reputation-aware verification.
Add one script tag and a <div class="sentinel-captcha"> to your form. The widget mounts itself — no build step.
Sentinel issues an adaptive proof-of-work challenge scored against the visitor's live IP reputation and behavior.
Your backend posts the token to /api/v1/verify and receives a passed / challenged / blocked outcome with a score.
A lightweight, self-contained checkbox that proves humanity without a single puzzle.
Preview only. Generate a site key in the Lab to embed the live widget on your own forms.
Get an API key and start protecting forms, logins and signups in minutes — with reputation intelligence the others can't match.
Sentinel API access is included on Dominion and higher plans. See plans & pricing.
