The Hardware Concurrency API is a feature in modern browsers that tells websites how many logical processors (also called CPU cores or threads) your device has. It can be accessed through navigator.hardwareConcurrency.

This API helps websites understand the computing power of your device so they can adapt accordingly. For example:

• A site running heavy tasks (like image editing or 3D rendering) can decide how many parallel threads to use.
• Web apps, such as online games or video editors, can balance performance by not overloading weaker devices.
• It allows developers to make their apps more efficient and responsive, especially when doing work in the background.

How Hardware Concurrency API Is Used / Risks

• Sites can combine this info with other fingerprinting data to narrow down what kind of device you're using. For example, a device listing 8 cores will appear more powerful - and less common - than one listing 2 cores. Because most users have devices with 4 to 8 logical cores, using values outside that range can make a profile stand out.

Most modern laptops typically report 4-8 logical cores, while many mobile devices report 2-4. This provides an excellent range of options for spoofing variations when switching between desktop-based and Android/iOS-based Kameleo profiles.

• If the value is unusual (too high, too low, mismatched with other signals), it may become a detection point.
• Because it can reveal some hints about your device’s performance level, browsers sometimes round or limit the value to reduce the risk of fingerprinting (websites piecing together many small details to uniquely identify you).

In short: The Hardware Concurrency API lets a website know how many “hands” (CPU threads) your device has to do work in parallel, so it can better adjust its performance without overloading your system.

Relevance to Kameleo

With Kameleo you can set Hardware Concurrency via the Local API, making your profile look more like a real device. This helps align concurrency with other fingerprint attributes and avoids exposing unusual values.