UUID Generator

Generate RFC 4122 compliant UUIDs instantly

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About UUID Generator

Generate cryptographically random UUID v4 identifiers with one click. Create up to 50 UUIDs at once, copy individually or in bulk, and choose between uppercase/lowercase and with/without hyphens. Essential for developers working with databases, APIs, distributed systems, and anywhere unique identifiers are needed. Runs entirely in your browser with no server calls.

UUID Generator Features

  • UUID v4 generation
  • Bulk generate up to 50
  • Copy single or all
  • Uppercase/lowercase toggle
  • With/without hyphens
  • Works offline
UUIDs (Universally Unique Identifiers) are 128-bit identifiers used across software engineering to uniquely tag records, sessions, API requests, and more. This UUID Generator creates RFC 4122 compliant v4 UUIDs using cryptographic randomness via your browser's crypto API. Generate single IDs or batch up to 50, toggle formatting options, and copy with one click. No server calls, no auth, no limits.

How Do I Use the UUID Generator?

Using the UUID Generator is straightforward:

Generate. Click the generate button to create one or more UUIDs. They appear instantly.

Configure. Choose how many UUIDs to generate (1-50), toggle uppercase, and remove hyphens if your use case requires it.

Copy. Click any UUID to copy it individually, or use the "Copy All" button to copy the entire batch to your clipboard, each on a new line.

Available features:

  • UUID v4 — cryptographically random
  • Bulk generation — up to 50 at once
  • Format options — uppercase, no hyphens
  • One-click copy — individual or batch

Understanding UUIDs

A UUID v4 looks like this: 550e8400-e29b-41d4-a716-446655440000. It's composed of 32 hexadecimal digits displayed in 5 groups separated by hyphens (8-4-4-4-12).

Collision probability: With 122 random bits, the probability of generating two identical UUIDs is astronomically low — you'd need to generate 2.71 quintillion UUIDs to have a 50% chance of one collision.

Common uses: Database primary keys, API request IDs, session tokens, file names, distributed system coordination, and message queues.

Privacy: UUIDs are generated entirely in your browser using crypto.randomUUID() or equivalent. No data leaves your device.

Tips for Best Results

Maximize your UUID workflow:

  • Use hyphens — Standard format is with hyphens. Only remove them if your system explicitly requires it.
  • Lowercase is standard — RFC 4122 recommends lowercase hex. Use uppercase only if your codebase convention requires it.
  • Batch for migrations — Need 50 UUIDs for seed data? Generate them all at once and paste into your migration script.
  • Bookmark this tool — Developers frequently need fresh UUIDs during development.

Step-by-Step Instructions

  1. 1Open the UUID Generator tool in your browser.
  2. 2Set the number of UUIDs to generate (1-50).
  3. 3Optionally toggle uppercase or remove hyphens.
  4. 4Click Generate to create your UUIDs.
  5. 5Click any UUID to copy it, or Copy All for the batch.

UUID Generator — Frequently Asked Questions

Is the UUID Generator free?+

Yes, completely free with no registration or limits.

Are these UUIDs truly unique?+

Yes. UUID v4 uses 122 bits of cryptographic randomness, making collisions virtually impossible.

Does this work offline?+

Yes, UUIDs are generated entirely in your browser with no server calls.

What version of UUID is generated?+

Version 4 (random), which is the most commonly used version in modern applications.

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