Developer Tools

UUID Generator

Generate single or bulk UUIDs (v4 random, v1 time-based) instantly. Copy individual IDs, generate a list of up to 1000, and download them as a .txt file. All generated locally using the Web Crypto API.

RFC 4122 v4 UUIDs Cryptographically random Generate 1–50 at once
5 UUIDs
.txt
  • Press "Generate" to create UUIDs

UUIDs generated using the Web Crypto API, entirely in your browser

Features

  • UUID v4 (random) and v1 (time-based) generation
  • Bulk generation: generate 1 to 1000 UUIDs at once
  • Uppercase or lowercase output toggle
  • With or without dashes format option
  • Copy single UUID or entire list with one click
  • Download list as .txt file

How to use it

  1. Select UUID version (v4 for most uses).
  2. Set quantity using the number input (default is 1).
  3. Click Generate, UUIDs appear instantly.
  4. Click a UUID to copy it, or use Copy All / Download.

Use cases

  • Generating database primary keys for new records
  • Creating unique IDs for distributed system messages
  • Seeding test data with unique identifiers
  • Generating correlation IDs for logging and tracing

Limitations

  • The generator uses browser UUID support when available.
  • Very large input can be slower on older devices.
  • This utility is designed for common snippets and local inspection, not as a full security or language-specific validator.
See also

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Questions & answers

Frequently asked

Are these truly random?

UUID v4 uses crypto.randomUUID() (or the Web Crypto API fallback) which produces cryptographically random output, suitable for security-sensitive IDs.

What is the difference between v4 and v1?

v4 is purely random. v1 is time-based and encodes the creation timestamp. For most uses, v4 is recommended as v1 UUIDs can leak server timing information.