99.5% identification accuracy*

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* based on typical website traffic, compared to 45% accuracy for free version


The creator of Fingerprint.js and Fingerprint2.js (used by thousands of companies) took feedback from existing open source users to create a new premium product: FPJS Pro. It is more than a JavaScript library. It's a platform for advanced fraud detection and prevention.

FPJS PRO is a combination of a client-side agent that runs in the browser and a server-side API that securely transmits to you all the information you need to detect unusual behavior. Identify malicious users, bots and other bad actors more effectively than ever before. Use our decision engine or incorporate the data we provide you into your own system.

Client-side agent

FPJS PRO does not calculate a fingerprint in the browser. Instead, it uses a lightweight and fast JavaScript agent that collects several device signals and securely sends them to our servers. This helps prevent reverse engineering and spoofing of a fingerprint by more advanced bots. The agent is hosted at edge locations around the world. It is only 7KB in size and always 20 ms away from your users.

Server-side identification API

Integrate with our APIs to receive identification events on your backend or get instant notifications about suspicious events. Data is never exposed in the browser. Identification information is transmitted securely to your servers.

History and analytics

Integrate our API into your ML pipeline or view the history of events in the FPJS dashboard. See all unusual activity and understand exactly what your visitors are doing. FPJS PRO stores a full history of identifications and visitor requests.

How to get started

Pro version was optimized for ease of use and requires only 2 simple steps to get started. Detailed API documentation is available for registered customers.

Add JavaScript snippet

Add this snippet as the first element inside the <head/> tag on every page you want to monitor for suspicious visitors. Pass configuration options to control the behavior of the data collection. We also accept custom data that can be passed-through or incorporated into our engine.

Register server-side webhook

Once you register your webhook, you will start receiving the events of your choice. Receive all activity or just suspicious events following your rules or ours.