One slider. Dual-stage AI scoring behind a closed backend. Verification in under 200ms. Zero frustration.
The actual Sentinel slider — drag right to pass
Our scoring engine lives entirely on the backend. You embed a script, users slide, and the verdict comes back — fast, clean, and invisible to anyone trying to reverse-engineer it.
On load, our JS silently collects behavioral signals: mouse movement, device fingerprint, timing patterns, browser environment. No user interaction required.
When verification is triggered, users see only a clean slider. Drag right to pass. The drag itself is analyzed: speed curve, micro-hesitations, trajectory smoothness.
Drag behavior is scored against the passive baseline. Mismatches — scripted movement, farm behavior, AI-mimicked curves — get flagged instantly.
The server returns a pass/fail with a confidence score. Your app logs it, gates the action, or flags the session. No opaque tokens, no guesswork.
One drag. The slider turns green or red. No image puzzles, no distorted text, no "select all crosswalks." Users don't even think about it.
Passive behavioral analysis on page load + active drag analysis after interaction. Both signals must agree. Two-layer defense that single-stage systems can't match.
See every verification: pass/fail rate, bot vs human split, geographic distribution, device breakdown. Know what fraction of your traffic is real.
No cookies, no fingerprinting, no PII collected. GDPR and WCAG 2.2 compliant. Your users' data stays yours — we're just the gatekeeper.
The scoring logic lives server-side. Clients get a verdict, never the model. No reverse engineering, no model extraction, no bypass by probing.
One script tag. One API call. Works with any stack — React, Vue, plain HTML, Node, Python. SDKs for the major languages. Docs you'll actually read.
One request = any call to our server, including page load and verification checks. All plans include full API access, the slider widget, and the dashboard.
Need higher volume? Talk to us — we'll work something out.
CAPTCHAs were built for a simpler time. Bots are smarter now, users are more impatient, and the cost of letting them through is higher than ever. Sentinel.dev was built for this moment. The slider that turns green when you're human. The algorithm that lives behind the curtain. The dashboard that shows you exactly who's real.
Stop letting bots through. Stop making humans solve puzzles. Start verifying what's real.