ToolBirch

UUID Generator

Generate RFC 4122 version 4 UUIDs using cryptographic randomness.Developer Tools

UUID generator

Generate RFC 4122 version 4 identifiers using your browser's cryptographically secure random source.

Between 1 and 100.

Click Generate to create identifiers. Nothing is stored or transmitted.

About this tool

Version 4 UUIDs are the default choice for identifiers that do not need to be sortable or tied to a machine. This tool uses the browser's cryptographic random source, never a Math.random-based approximation.

How to use the UUID Generator tool

  1. Choose a count. Pick how many identifiers to generate, from 1 up to 100 at a time, and tick Uppercase if you need it.
  2. Generate. Click Generate. Each value is produced with crypto.randomUUID and shown as a plain list.
  3. Copy. Use Copy all to take the whole batch to your clipboard.

Supported formats

Input

  • A count between 1 and 100

Output

  • RFC 4122 version 4 UUIDs
  • A copyable plain-text list

Inputs are validated before anything is processed. Invalid values and unsupported files are rejected with a clear error instead of failing silently.

Frequently asked questions

Are these real version 4 UUIDs?

Yes. They come from crypto.randomUUID, which uses a cryptographically secure random source and sets the version and variant bits correctly.

Can I get uppercase UUIDs?

Yes. Tick the Uppercase checkbox before generating. The default is lowercase, which is the conventional form.

Are the values stored or reused?

No. Every click produces fresh values and nothing is kept after you leave the page.

Why a limit of 100?

It keeps the page responsive on mobile devices. You can click again for another batch.

Privacy

Everything you enter stays in this browser tab. There is no upload endpoint for tool inputs, no account, and no server-side copy of your text or files. Results are produced locally and disappear when you close the page.

No account is required and no file is ever uploaded. See the privacy policy for details about analytics and the limited data this site stores.

Known limitations

  • Only version 4 (random) UUIDs are produced; v1, v5 and v7 are not offered.
  • Batches are capped at 100 values per click.
  • crypto.randomUUID requires a secure context (HTTPS or localhost).

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