HWID license lock: one key, one computer

How HWID locking works

When your app starts, the SDK reads a stable machine identifier — the Windows MachineGuid, Linux /etc/machine-id, or macOS platform UUID — and hashes it with SHA-256. Only that hash ever leaves the computer.

On first activation the server binds the key to the hash. On every later run it compares: same hash, valid; different hash, refused with a signed “different device” answer. See the device-ID specification for the exact algorithm, so you can implement it in any language.

Devices change — so resets are built in

• A customer who bought a new PC opens the license check page, enters their key and asks for a reset.
• You review the request in your dashboard (or get an e-mail) and approve it in one click; the key unbinds and locks to the next device that activates it.
• Every reset is logged, and keys used on several devices raise an alert so you can spot sharing early.

Privacy and honesty

The raw machine ID never leaves the device and cannot be reversed from the hash. A determined attacker with full control of a machine — using a virtual machine or a spoofed ID — can still work around any client-side check; device locking stops casual sharing and key resale, which is where most losses happen.