API Key Generator

What this tool does

API Key Generator creates cryptographically secure random API keys using crypto.getRandomValues(), in hex, base64url or UUID v4 format, with a configurable prefix (like sk_live_), adjustable randomness length, and bulk generation of up to 500 keys at once.

Provisioning test or development API keys for a new service, a set of test accounts, or a mock integration often just needs a batch of sufficiently random, uniquely formatted strings, without needing an actual backend system running yet.

This generator creates cryptographically secure random keys using crypto.getRandomValues(), in your choice of hex, base64url or UUID v4 format, with an optional prefix matching common real-world conventions (like sk_live_ or sk_test_), and can generate up to 500 keys at once for bulk test data.

How to use API Key Generator

1. Choose a Format: Hex, Base64url, or UUID v4.
2. Optionally set a Prefix.
3. For hex/base64url, set the number of Random bytes.
4. Set How many keys to generate a batch.
5. Copy individual keys, or copy/download the whole batch.

Tips for better results

• A 24-byte (192-bit) key, the default, is already far beyond any realistic brute-force range; increasing it further adds negligible practical security but makes the key longer to handle.
• Hex and base64url formats are common for API keys and bearer tokens; UUID v4 is more common for resource identifiers or simpler internal API keys.
• A prefix like sk_live_ or sk_test_ (a pattern popularised by Stripe) makes it easy to visually distinguish key types or environments at a glance, and helps automated secret-scanning tools recognise the key format.
• For real production credentials, generate and store keys on your backend using its own secure key management, not a browser tool; this is intended for test/development data and understanding key formats.

Common use cases

• Generating placeholder API keys for a new service’s test environment.
• Creating a batch of unique test credentials for multiple mock accounts at once.
• Understanding the difference between hex, base64url and UUID key formats.
• Quickly generating a single random token for a one-off scripting or testing need.

Common mistakes to avoid

• Using generated keys as real, production-issued credentials; your backend should generate and store actual API keys itself, with proper hashing, rotation and revocation support, none of which a stateless browser tool provides.
• Choosing an unnecessarily small byte count for something that needs to resist guessing; 16 bytes (128 bits) is a reasonable minimum, 24-32 bytes gives extra headroom for long-lived credentials.
• Assuming UUID v4 keys are as compact or convention-matching as hex/base64url for typical bearer-token-style API keys; UUIDs are more commonly used as resource IDs than as secret tokens in most API conventions.