UUID Generator for Developers

Produce v4 UUIDs in bulk, with the option to copy one straight to the clipboard.

Tools for engineers who would rather not context-switch into yet another tab to validate a JWT or generate a UUID. Everything runs in your browser, your payloads never leave the machine, and the pages load fast enough that you can leave them open in a sidebar while you debug.

Open the UUID Generator →

What it does for Web and API developers

How to use it

  1. Pick how many IDs you need and which output format (single line, comma list, SQL VALUES).
  2. Click generate. The randomness is sampled without modulo bias, so every possible 128-bit value is equally likely.
  3. Copy the result and paste into your migration script, your fixture, or your SQL seed file.

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Common questions

Should I use a random UUID as a database primary key?

It works, but random v4 keys are not ordered, so every insert lands in a different part of the index and large tables fragment. If insert throughput matters, prefer a time-ordered identifier and keep the UUID as the public-facing reference instead of the storage key.

Is the value generated here cryptographically random?

It uses the browser crypto API rather than a seeded pseudo-random generator, which is the distinction that matters when the identifier has to be unguessable. Do the same in your own code: Math.random-based UUIDs are not safe for anything a user could enumerate.

Can a UUID leak information about the record it identifies?

A random v4 value carries no time, host or sequence information, which is why it is a reasonable choice for a public id. Time-based v1 and sortable v7 values do embed a timestamp, and v1 historically included a node identifier - do not expose those where the timing itself is sensitive.