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UUID Generator

Generate version 4 UUIDs (Universally Unique Identifiers) instantly. Generate up to 20 at once and copy with one click.

Click "Generate" to create UUIDs.

Frequently Asked Questions

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify objects in software. Version 4 UUIDs are randomly generated.

Are the UUIDs truly unique?

UUID v4 uses random numbers, making collisions astronomically unlikely. There are 2¹²² possible v4 UUIDs.

What are UUIDs used for?

UUIDs are used as database primary keys, API resource identifiers, session tokens, correlation IDs in distributed systems, and unique filenames.

What is the difference between a UUID and a GUID?

A GUID (Globally Unique Identifier) is Microsoft's name for essentially the same concept. They follow the same format and are interchangeable in most contexts.

Can I use these UUIDs in production?

Yes. The UUIDs are generated using a cryptographically seeded random function and conform to the RFC 4122 standard for UUID v4.

UUID Generator — Generate Version 4 UUIDs Instantly Online

A UUID (Universally Unique Identifier) is a 128-bit value used to uniquely identify records, objects, and resources in software systems. Version 4 UUIDs are randomly generated using a standardized format: eight hexadecimal characters, followed by three groups of four, followed by twelve — all separated by hyphens (e.g., 550e8400-e29b-41d4-a716-446655440000).

With 2¹²² possible values — approximately 5.3 undecillion — the probability of generating the same UUID twice is astronomically small. You could generate a trillion UUIDs per second for the next billion years and the chance of a collision would still be negligible. This makes UUID v4 ideal for any system that needs to assign unique identifiers without central coordination.

UUIDs are used as primary keys in relational and NoSQL databases, filenames for user-uploaded content, resource identifiers in REST APIs, session tokens, correlation IDs in distributed tracing systems, and any scenario where uniqueness matters across multiple independent systems.

Unlike sequential integer IDs, UUIDs can be generated offline, on multiple machines simultaneously, without any risk of duplication. This is particularly valuable in distributed architectures, event-driven systems, and mobile apps that need to create records before syncing to a server.

Generate up to 20 UUIDs in a single click and copy any or all of them instantly.

How to Use the UUID Generator

  1. Select how many UUIDs you want to generate (1 to 20).
  2. Click "Generate".
  3. Click "Copy" next to any individual UUID to copy it to your clipboard.
  4. Or click "Copy All" to copy the complete batch at once.

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