Generate cryptographically secure random numbers, passwords, UUIDs and string sequences for testing, demos and security needs.
Many random tools use the predictable Math.random API. Ours uses the Web Crypto API, the same primitive your bank uses to mint session tokens.
Passwords, API keys and session tokens must come from a cryptographically secure random number generator (CSPRNG), not Math.random(). Our password generator uses the browser's crypto API for unpredictable output.
UUIDs identify database records and distributed systems. Version 4 UUIDs are random. Use them when you need unique IDs without a central allocator. Random strings are also handy for test fixtures and placeholder data in development.
They are cryptographically secure pseudo-random, drawn from the operating system's entropy pool via the Web Crypto API. That's the strongest standard available in the browser.
Yes, the values never leave your device. That said, for production systems prefer a password manager so the value is stored as it's generated.
v4 is fully random. v7 prefixes the random portion with a millisecond timestamp, which sorts naturally, useful as a primary key in databases.
Theoretically yes, practically no. The probability of two UUID v4s colliding is about 1 in 2¹²², you would need to mint a billion per second for 85 years to have a 50% chance.