Mr. Encoder

UUID / GUID Generator

Generate random v4 or time-ordered v7 UUIDs in bulk, and inspect any UUID's version, variant and timestamp.

How to use

  1. Choose v4 (random) or v7 (time-ordered) and how many UUIDs you need (up to 1000).
  2. Set the format: uppercase, with or without hyphens, or wrapped in braces like a Microsoft GUID.
  3. Copy all UUIDs or download them as a .txt file; paste any UUID into the inspector to check its version and timestamp.

Frequently asked questions

What is a UUID (GUID)?

A UUID (Universally Unique Identifier), called GUID in the Microsoft world, is a 128-bit identifier written as 32 hex digits such as 550e8400-e29b-41d4-a716-446655440000. It can be generated anywhere without a central authority and is practically guaranteed to be unique.

Should I use UUID v4 or v7?

v4 is fully random and reveals nothing about when it was created. v7 begins with a millisecond timestamp, so new IDs sort in creation order, which keeps database B-tree indexes compact; prefer v7 for primary keys and v4 when the creation time should stay hidden.

Can two generated UUIDs ever collide?

In theory yes, in practice no. A v4 UUID has 122 random bits, so you would need to generate about 2.7 quintillion UUIDs to reach a 50% chance of a single duplicate.

Are these UUIDs generated securely?

Yes. They are created in your browser with the Web Crypto API (crypto.randomUUID / crypto.getRandomValues), a cryptographically secure random source, and are never sent to a server.

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