Free Online API Key Generator

1. Pick the output format — hex, Base64, Base62 or alphanumeric.
2. Drag the length slider to choose how many characters long the key should be.
3. Optionally add a prefix like "sk_live_" so the key advertises its type.
4. Set How many? and click Generate. Copy each key with its button.

An API key is a random string a client sends with each request to identify itself and authorise access. Strength comes purely from unpredictability — a key drawn from `crypto.getRandomValues` with 128 or more bits of entropy is effectively unguessable. This generator picks the encoding (hex per RFC 4648 §8, Base64 per RFC 4648 §4, Base62 for url-safe compactness, or alphanumeric for human-friendliness) and lets you set length and prefix.

Prefixes like `sk_live_`, `ghp_` or `xoxp-` make secret-scanning tools far more effective. GitHub's secret scanning, Trufflehog, Gitleaks and similar tools rely on these signatures to detect keys committed to public repos and trigger automatic revocation.

Server-side best practices: hash keys before storing them (SHA-256 is fine here since the secret already has high entropy, or HMAC-SHA256 with a server-side pepper for defense in depth), compare in constant time to defeat timing attacks, and rotate on any suspicion. Never log raw keys, never put them in URLs, and never embed them in client-side bundles. Generated keys are not stored here — copy and place them in your secret manager immediately.