What is a UUID?
A UUID is a 128-bit identifier commonly used to identify records or resources. This tool generates UUID version 4 values using your browser's cryptographically secure random number generator when available.
What a UUID is and when to use one
A UUID is a 128-bit identifier commonly used to distinguish records or resources without relying on a central sequence. This page generates version 4 UUIDs, whose values are based on random data. They are suitable for test fixtures, local development, and ordinary record identifiers where a random UUID is an appropriate choice.
Choose an output shape
Generate one or more values, then select either one UUID per line or a JSON array. The line format is easy to paste into a list; the JSON array can be used directly where a JSON value is expected. Use the copy action for quick transfer or download the generated text when you need a local file.
Keep identifiers in context
A UUID identifies a value; it does not carry the record's meaning or access rules. Do not treat a UUID as a password, API key, or authorization token. If an application needs a secure secret or a specific identifier format, use the generator and security guidance recommended by that application.
UUIDs are designed to make accidental collisions very unlikely, but no random identifier is a substitute for enforcing uniqueness in the system that stores it.