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UUID Generator

Generate random v4 or time-ordered v7 UUIDs in bulk.

  • 100% Free
  • No Sign Up
  • Works in Your Browser

UUID generator

Generate random v4 or time-ordered v7 UUIDs

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How to use the UUID generator

Three steps, all in your browser.

  1. 1

    Choose what you need

    Pick the type and how many. Results appear straight away.

  2. 2

    Set the options

    Choose the length, count or algorithm. The output updates instantly.

  3. 3

    Copy the result

    Copy the output in one click. Nothing is saved or sent anywhere.

UUID Generator: what to know

The UUID generator creates universally unique identifiers in bulk using your browser's cryptographically secure random generator. Choose version 4, which is 122 random bits, or version 7, defined in RFC 9562 (2024), which starts with a 48-bit Unix timestamp in milliseconds followed by random bits.

A UUID is 128 bits written as 32 hex digits in five groups (8-4-4-4-12). The first digit of the third group is the version: 4 or 7 here. Because v7 values begin with the time, they sort in creation order, which keeps database B-tree indexes compact and inserts fast; random v4 keys scatter inserts across the index. Both are unique for practical purposes: you'd need billions of billions of v4 UUIDs before a duplicate becomes likely.

A v7 UUID reveals roughly when it was created, which matters if IDs are public and creation times are sensitive. Microsoft calls UUIDs GUIDs; they're the same format. The generator also makes ULIDs (26-character, time-ordered) and NanoIDs, and can inspect a pasted UUID or ULID to show its version and embedded time.

Popular uses

  • Primary keys and IDs for test and seed data
  • Idempotency keys for API requests
  • Correlation IDs for logs and tracing
  • Unique file names and object keys

Tips for the best result

  • Prefer v7 for new database primary keys; use v4 when the ID must not leak timing.
  • Store UUIDs in a native uuid column (PostgreSQL) or as 16 bytes, not as 36-character text, where you can.
  • UUIDs are not secrets: don't use them as passwords or unguessable tokens for access control.

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Frequently asked questions