Privacy-First Bot Protection · SaaS

Stop bots. Not
your users.

SliderCAPTCHA reliably protects your forms from bots using a simple, intuitive slider interaction that real users understand instantly. No image puzzles. No tracking profiles. No frustration.

No cookies or tracking GDPR-compliant by design Works on any backend
Live Preview
Slide to verify you're human
← Drag the slider to the right →
Verified - human interaction detected
❌ Traditional CAPTCHA
Distorted text
Image puzzles
Tracking & cookies
✓ SliderCAPTCHA
One intuitive gesture
No puzzles needed
Zero tracking data
Works with →
PHP Node.js Python Ruby .NET / C# Java Go Rust
Why SliderCAPTCHA

More security. Better UX.
Full control.

Traditional CAPTCHAs are cumbersome, hurt conversion rates, or raise serious privacy concerns. SliderCAPTCHA relies on a clear, human interaction that effectively blocks automated attacks - while remaining fast, accessible, and pleasant to use.

🤝

User Friendly

Intuitive slider instead of image challenges. Self-explanatory - no instructions required. Works seamlessly on desktop and mobile devices.

🤖

Effective Bot Protection

Reliably detects automated access. Distinguishes human behavior from machine behavior. Protects against spam, form abuse, and automated attacks.

🔒

Privacy-First by Design

No sharing of user data. No advertising or tracking profiles. GDPR-compliant by design with zero cookies - ideal for privacy-sensitive environments.

Flexible Usage

Ideal for contact forms, login pages, registrations, and web apps. Suitable for small websites and high-traffic platforms alike.

☁️

Fully Managed SaaS

We handle operation, scaling, and maintenance. No infrastructure required on your side. Ready to use immediately after signup.

🛟

Secure Fallback

If the service is ever unavailable, your forms will not be blocked. Built-in fallback logic ensures zero downtime impact on your users.

Controlled Flow

Validate. Verify. Accept.

SliderCAPTCHA doesn't force itself into your process. It appears only at the right moment - after your own validation is complete - keeping your business logic untouched and the user experience clean.

01

Form Validation

Your application validates all input fields as usual. SliderCAPTCHA only appears when your own validation passes - eliminating unnecessary CAPTCHA challenges for users who haven't completed the form yet.

Your logic first Clean UX
02

Slider Challenge

A lightweight JavaScript embed presents the slider interaction. The user drags the handle to the end. Human movement patterns are analyzed client-side and a signed token is generated on success.

Client-side challenge Signed token
03

Server Verification

Your backend sends the token to our verification API via a simple cURL request. We return a pass/fail result. You decide what happens next. The final decision always stays within your application.

cURL API call You're in control

Ready to protect your forms?

Get started in minutes - no SDK required, no infrastructure to manage.

Key Benefits

Built for developers.
Loved by users.

Every aspect of SliderCAPTCHA is designed to maximize security while minimizing friction for real users.

📋

Contact & Inquiry Forms

Protect your most critical touchpoints from spam and automated submissions without adding friction for genuine leads.

🔑

User Registration & Login

Prevent credential stuffing and automated account creation with a challenge that bots reliably fail and humans barely notice.

📬

Newsletter Sign-ups

Keep your mailing lists clean and your open rates high by blocking fake sign-ups at the source before they pollute your data.

🏢

Agencies & Multi-Client Projects

Manage multiple client domains under one account. Simple sitekey management per domain or subdomain - no extra overhead.

🚀

SaaS Platforms

Scale-ready from day one. Our infrastructure handles request spikes automatically. Fair-Use policy means no hard shutdowns during traffic peaks.

🏛️

Enterprise & Public Sector

Suitable for security-critical forms in regulated industries. GDPR-compliant, no IP logging, no cookies - passes even strict privacy audits.

Easy Integration

One script. Any backend.

Integration requires a single JavaScript embed on the client side and one cURL request on the server side. No mandatory SDK, no proprietary libraries. If your environment can send HTTP requests, it works with SliderCAPTCHA.

Client-side embed (HTML)
<!-- Add before </body> --> <script src="https://slidercaptcha.dslm-itconsulting.com/embed.js" data-sitekey="your_public_key" data-mode="live" data-language="en"></script> // Trigger after your validation passes: SliderCaptcha.execute() .then(resp => submitWithToken(resp.token)) .catch(() => showError());
Server-side verification (PHP)
$ch = curl_init('https://slidercaptcha.dslm-itconsulting.com/api/v1/verify.php'); curl_setopt_array($ch, [ CURLOPT_POST => true, CURLOPT_RETURNTRANSFER => true, CURLOPT_POSTFIELDS => json_encode([ 'token' => $_POST['slidercaptcha_token'], 'secret_key' => 'your_secret_key' ]) ]); $result = json_decode(curl_exec($ch), true); if ($result['success']) { /* process form */ }

Integration examples

Step-by-step guides for classic HTML forms and modern AJAX flows:

Supported languages

PHP Node.js Python Ruby Java .NET / C# Go Perl Rust

Any environment that supports cURL-based HTTP requests works with SliderCAPTCHA. No SDK required.

Privacy & Compliance

Privacy-first.
By design - not by accident.

SliderCAPTCHA was built from the ground up with European data protection standards in mind. There are no hidden data flows, no profiling, no advertising components.

🚫

No Personal Data Stored

We do not store, process, or transfer any personal data. Verification tokens are ephemeral and contain no user identifiers.

🍪

Zero Cookies

SliderCAPTCHA sets no cookies of any kind - neither session cookies, tracking pixels, nor persistent identifiers.

📍

No IP Logging

We do not log, store, or analyze IP addresses. Your users' network identity stays entirely outside our systems.

📊

No Advertising Profiles

We have no advertising business. There is no monetization of user behavior data - ever.

🇪🇺

GDPR-Compliant

Designed to meet EU GDPR requirements out of the box. Suitable for regulated industries, public sector, and enterprise applications.

🛡️

Secure Fallback

If our service is temporarily unavailable, your forms continue to work. The fallback is verified server-side to prevent bypass attacks.

Localization

18 languages. One integration.

SliderCAPTCHA automatically adapts to your users' language. Simply set data-language in the embed script.

ar Arabic
cs Czech
da Danish
de German
en English
es Spanish
fi Finnish
fr French
it Italian
ja Japanese
ko Korean
nl Dutch
pl Polish
pt Portuguese
ru Russian
sv Swedish
tr Turkish
zh Chinese (Simplified)
Pricing

Simple, domain-based pricing.

Every plan includes a 30-day free trial. Upgrade, downgrade, or cancel anytime.

Need more domains or a custom SLA?

Enterprise plans include dedicated support, custom domain limits, and a service level agreement.

FAQ

Common questions.

Everything you need to know before getting started.

Do I need to install anything server-side?

No installation required. Client-side is a single <script> embed. Server-side is one cURL API call in your existing backend - no SDK, no framework dependency.

What if the SliderCAPTCHA service goes down?

Your forms will not be blocked. SliderCAPTCHA includes a secure fallback mechanism. Your backend verifies server-side whether the service is genuinely unavailable before allowing bypass - preventing attacks that exploit downtime.

Is it really GDPR-compliant?

Yes. No personal data is stored, no cookies are set, no IP addresses are logged, and there are no advertising or tracking components. Suitable for privacy-sensitive environments and public sector use.

How does a "sitekey" work?

Each domain or subdomain you want to protect gets a unique public sitekey. You embed this key in the client-side script. Your secret key is only used server-side for verification - never exposed to the browser.

Can bots simply replay a valid token?

No. Tokens are signed, single-use, and time-limited. Replay attacks are detected and rejected by the verification API. Each successful slider interaction produces a unique, non-reusable token.

What happens during traffic spikes?

We operate a Fair-Use policy - no hard shutdowns during short-term spikes. The service stays active. For sustained higher usage, we reach out proactively to recommend an appropriate plan upgrade.

Does it work with WordPress or other CMS?

Yes. SliderCAPTCHA works with any web environment that can load JavaScript and make HTTP requests. WordPress, Joomla, custom PHP, Node.js, Python - all supported.

Can I manage multiple client projects?

Yes. Agencies can manage multiple sitekeys under one account. Each domain or subdomain gets its own key, making client isolation clean and straightforward.

Contact

Get in touch.

Whether you have questions about plans, need a custom volume, or just want to discuss your use case - we're happy to help. We respond quickly.