CAPTCHA Protection
Invisible human verification that protects your forms without frustrating your users. No puzzles. No image grids. Just security.
Experience Invisible CAPTCHA
Fill out this form normally - no puzzles or images to solve. Watch as SilentAuth analyzes your behavior in real-time.
Try the Demo
Fill out this form - no CAPTCHA puzzles!
Live Behavior Signals
These signals are being collected invisibly as you interact with the form.
As you fill out the form, SilentAuth analyzes your mouse movements, typing patterns, and interaction timing. Bots can't replicate natural human behavior, so they get low scores and are blocked - while real users sail through without seeing any challenges.
Why Choose Invisible CAPTCHA?
SilentAuth uses behavioral analysis, device fingerprinting, and risk scoring to distinguish humans from bots - all without user interaction.
Zero Friction
Real users never see a challenge. Verification happens invisibly in the background using behavioral signals.
GDPR Compliant
No tracking cookies, no cross-site identifiers, no data selling. Privacy-first architecture.
99.9% Accuracy
Industry-leading detection rates with minimal false positives through ML-powered risk scoring.
How to Integrate
A complete step-by-step guide to implementing invisible bot protection on your forms.
Add Script to Your Page
Include the SilentAuth script on pages with forms you want to protect. One line of code, async loading.
<script src="https://sdk.silentauth.com/captcha.js" data-project="your-project-id" async></script>
User Interacts Normally
As users browse and fill out your form, SilentAuth silently analyzes behavioral patterns, device signals, and interaction timing.
Get Verification Token
When the user submits the form, call verify() to get a cryptographic token proving they're human.
const token = await SilentAuth.verify({
action: 'contact_form'
});
// Include token in your form submission
formData.append('sa_token', token);Validate on Your Server
Send the token to your backend. Make a server-side API call to validate it before processing the form.
// Server-side validation (Node.js example)
const response = await fetch(
'https://api.silentauth.com/v1/verify',
{
method: 'POST',
headers: {
'Authorization': 'Bearer YOUR_SECRET_KEY',
'Content-Type': 'application/json'
},
body: JSON.stringify({ token: req.body.sa_token })
}
);
const result = await response.json();
if (result.success && result.score >= 0.5) {
// Process the form - user is human
} else {
// Block submission - likely a bot
}Action Processed
If validation passes, process the form normally. Bots are blocked, real users sail through without ever seeing a challenge.
SilentAuth vs Traditional CAPTCHA
See why invisible verification is the future of bot protection.
| Feature | SilentAuth | Traditional CAPTCHA |
|---|---|---|
| User friction | None | High - puzzles/images |
| Mobile experience | Seamless | Poor - tiny images |
| Accessibility | Full - no visual challenges | Limited - audio fallback |
| Bot detection | Behavioral + ML | Image recognition |
| Privacy | No tracking cookies | Cross-site tracking |
Common Use Cases
Protect any form or user interaction from automated abuse.
- Login and registration forms
- Contact and lead generation forms
- E-commerce checkout protection
- Comment and review spam prevention
- Newsletter signup protection
- Password reset forms
// Frontend: React form example
import { SilentAuth } from '@silentauth/sdk';
function ContactForm() {
const handleSubmit = async (e) => {
e.preventDefault();
// Get verification token
const token = await SilentAuth.verify({
action: 'contact_form'
});
// Submit with token
await fetch('/api/contact', {
method: 'POST',
body: JSON.stringify({
...formData,
sa_token: token
})
});
};
return <form onSubmit={handleSubmit}>...</form>;
}Ready to protect your forms?
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