The Invisible Shield Against Bots

Originally proposed by Adam Back in 2002, HashCash leverages a brilliant concept: it demands a complex calculation embedded in your form, one so computationally intensive (requiring hundreds or thousands of attempts to solve) that bots or malicious scripts would waste prohibitive amounts of processor time trying to crack it. When a user arrives at your form, the calculation runs silently in the background, completed automatically via JavaScript. The server then verifies the solution with a single, lightning-fast check—if correct, the user proceeds; if not, the submission fails. Bots relying on Python scripts or basic automation? They’re out of luck—they must use a JavaScript-enabled browser to pass, making form abuse a thing of the past.

Seamless and User-Friendly Captcha

The beauty of "Captcha - HashCash" lies in its invisibility. Your users won’t see or interact with it—it happens effortlessly behind the scenes, ensuring a frictionless experience. Whether they’re submitting a contact form, registering, or reporting a bug, they’ll enjoy a smooth process while your site remains protected. Want to see it in action? Visit our bug reporting page (link below)—while you won’t notice the CAPTCHA itself, watch your process monitor (e.g., top in Linux) to catch a CPU spike as the calculation runs!

Simple, Powerful Configuration

Setting up "Captcha - HashCash" couldn’t be easier. Open the plugin, choose your desired difficulty level—ranging from 1 (minimum) to 4 (maximum)—to balance security and performance. For an extra layer of protection, enable the optional delayed calculation feature: the script waits until the user interacts with the form, foiling bots that rush submissions or linger too long. Bots waiting for the CAPTCHA? They’ll wait forever. Bots submitting too quickly? They’ll miss the mark.

Privacy-First Design for GDPR Compliance

In an era of stringent privacy regulations like the GDPR and EU e-Privacy Directive, "Captcha - HashCash" stands out as an ideal solution. Traditional CAPTCHAs often rely on external services (e.g., Google reCAPTCHA), which can introduce third-party cookies and tracking mechanisms—potential headaches for website owners aiming to comply with EU laws. HashCash eliminates these concerns entirely. By operating solely within your site’s JavaScript environment, it avoids external dependencies and prevents additional cookies from being placed on user systems. This self-contained approach not only enhances user trust but also simplifies compliance with privacy standards, making it a go-to choice for privacy-conscious developers and businesses.

Cutting-Edge Captcha Technology

2002 meets 2025

Powered by the Web Cryptography API and Subtle.Crypto, "Captcha - HashCash" harnesses modern JavaScript capabilities to deliver a lightweight, efficient solution. No third-party dependencies, no server strain—just robust, autonomous protection for your Joomla forms.

Protect your Joomla forms effortlessly with "Captcha - HashCash"—the painless, invisible CAPTCHA that keeps bots at bay while delighting your users by NOT making them do tricks like trained animals.

Features

• Configurable Difficulty: Adjust the calculation intensity from 1 to 4 for optimal security.
• Invisible Protection: No mangled text, math problems, or user interaction—just seamless defense.
• Automatic Completion: Runs silently in the background with JavaScript.
• Bot-Proof Design: Requires a JavaScript-enabled browser, thwarting automated scripts.
• Delayed Calculation (Optional/Default): Foils bots by timing the calculation to user interaction.
• Modern Tech: Leverages Web Cryptography API for efficient, cutting-edge security.
• Bot Countermeasures (Optional): When a bot is detected, the calculation becomes unsolvable.
• Privacy-Friendly: No external services or cookies, ensuring GDPR and EU e-Privacy Directive compliance.