API key generator — prefixed, high-entropy keys
Generate random API keys with a recognisable prefix and strong entropy, in bulk. Every key comes from your browser's secure random source (0 uploads, works offline).
How to use it
- Set the options above.
- Results generate instantly on your device.
- Copy or Download them.
FAQ
How do I generate a secure API key for free?
Set a prefix and entropy, and keys generate instantly in your browser from crypto.getRandomValues, with no upload. A prefix like sk_ makes a key self-describing and easy to grep; the random tail makes it unguessable.
Why add a prefix like sk_ or pk_?
A prefix tells you at a glance what a key is (secret vs public) and lets you scan logs and code for leaked keys. It is the pattern Stripe popularised — the prefix is metadata, the random part is the secret.
Are the keys generated on a server?
No — entirely in your browser, so a key you take was never seen by anyone else's infrastructure. Turn off your Wi-Fi and it still works.
How random are they?
They use the cryptographically secure random generator, base62-encoded, with the entropy in bits shown so you can judge strength.
Limits
Generates opaque random keys; it does not register them with any service. Store them securely — they are not recoverable here.
Related
The password generator and UUID generator share the same secure random source.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.