What it is
navigator.hardwareConcurrency reports how many logical processors the browser may use — physical cores times threads, sometimes capped by the browser. It exists so pages can size worker pools, and it leaks a little about the machine in the process.
How websites read it
navigator.hardwareConcurrency // 8One property, one integer. There is nothing to compute; the interesting part is whether the number fits the rest of the machine.
Why it identifies you
A core count carries only a few bits of entropy on its own, but it is stable and it correlates with the device class: phones sit at 4–8, laptops at 8–16, workstations higher. As a cross-check it helps decide whether the claimed hardware is real.
How risk-control systems use it
Risk engines look for values no shipping CPU reports (0, 3, 128+), odd counts on x86 parts that always hyper-thread, and counts that contradict the GPU or device class. Many virtual machines and headless farms also share one telling number across thousands of sessions.
Common mistakes
Typing a number instead of picking one from real hardware; the same count on every profile; a 64-core value next to an integrated GPU and 4 GB of memory.
Mango is accepting waitlist registrations. These capabilities describe its first release; client access opens with invitations.
How Mango Browser handles it
CustomDrawn from the values real desktops report (2 to 64), so the count always matches shipping hardware.
Check yours
Jump to this signal in your scan results.