Online UUID Generator & GUID Generator

Generate browser-local UUIDs and GUIDs for request IDs, fixture batches, and sortable v1 samples.

Options
Generated UUIDs 0
Generating a fresh UUID batch in your browser...
Copy-Ready Helpers
Request Header Lines
Quoted UUID Lines
JSON ID Objects
UUID / GUID Workflows
Single request ID
v4 路 1 路 Newline List
Generate one browser-local UUID v4 / GUID for request headers, trace IDs, and quick copy-paste handoffs.
Fixture batch JSON
v4 路 8 路 JSON Array
Generate a UUID v4 batch that is ready for JSON arrays, fixture files, and seed-data drafts.
Sortable v1 sample
v1 路 5 路 Newline List
Generate browser-local UUID v1 samples when you want timestamp ordering for debugging or migration rehearsals.
What is a UUID or GUID?

A UUID (Universally Unique Identifier), also called a GUID (Globally Unique Identifier), is a 128-bit value used to identify records, requests, and resources across systems. The common text form uses 32 hexadecimal characters split into five groups with hyphens.

How this UUID / GUID workflow works

This page keeps the workflow query-backed for presets, version, count, and output mode, then generates fresh UUIDs in the browser from those settings. UUID v4 is the default for request IDs and public-facing identifiers. UUID v1 keeps timestamp ordering for sortable samples, and browser-side generation uses a random node id because browsers do not expose MAC addresses.

Common Use Cases
  • Request and correlation IDs in APIs
  • Seed data and test fixture batches
  • Sortable migration or debugging samples
  • Database and resource identifiers
  • Unique IDs for logs, queues, and job traces
UUID Version Comparison
v1 Time-ordered: Best when you need sortable samples. Browser-side generation uses timestamp ordering plus a random node id.
v4 Random: Best default for request IDs, fixtures, and public identifiers because it does not expose timing or machine details.
Frequently Asked Questions

Are UUIDs truly unique?

While collisions are theoretically possible, the probability is astronomically low (1 in 2^122 for v4). You would need to generate 1 billion UUIDs per second for 85 years to have a 50% chance of collision.

Should I use UUID v1 or v4?

Use v4 for most request IDs, fixtures, and public identifiers. Use v1 when sortable samples help your workflow and creation-time ordering matters more than hiding that timing signal.