ToolNova

💻 UUID Generator (v4) — bulk unique identifiers

Generate cryptographically random version 4 UUIDs in bulk — up to 100 at a time. Choose uppercase formatting or strip the hyphens, then copy them all in one click. Everything is produced by your browser’s secure random generator.

Developer Free · no sign-up Added 2026-07-31
Input
Result

Private by design. This tool runs entirely in your browser — nothing you enter or add is uploaded to any server.

How it works

  1. Click Generate (or change any option) to create a fresh batch of version 4 UUIDs.
  2. Each UUID is 128 bits: 122 of them are filled by your browser’s cryptographically secure random generator, the rest mark the version and variant.
  3. Toggle uppercase or hyphen-free formatting — the underlying identifier is identical, only the display changes.
  4. Copy the whole list with the Copy button; each line holds one UUID.

Examples

  • A standard v4 UUID looks like 3f6b2a1e-8c4d-4e7a-9f1b-2c5d8e0a4b6f.
  • Need IDs for a database seed? Generate 50 at once and paste them straight into your fixtures.
  • With hyphens removed you get 3f6b2a1e8c4d4e7a9f1b2c5d8e0a4b6f — handy for URLs and filenames.

Frequently asked questions

What is a UUID?

A universally unique identifier is a 128-bit value standardized by RFC 9562. Version 4 UUIDs are randomly generated, so the chance of two identical UUIDs ever being created is astronomically small — you can safely treat them as unique.

Are these UUIDs cryptographically secure?

Yes. They are produced with your browser’s crypto.getRandomValues (or crypto.randomUUID where available), not the predictable Math.random, so they are suitable for security-sensitive identifiers.

What is the difference between a UUID and a GUID?

They are effectively the same thing — GUID is Microsoft’s name for the UUID format. A GUID from this tool can be used anywhere a .NET or Windows GUID is expected.

Can two generated UUIDs ever collide?

In practice, no. With 122 random bits you would need to generate about 2.7 quintillion UUIDs to have a 50% chance of a single collision. Generating a billion per second would take decades.

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