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UUID Generator

Generate RFC 4122 compliant UUIDs (Universally Unique Identifiers)

Generated UUID:

Bulk Generation

How to use the UUID Generator

To generate a UUID, open the UUID generator and it instantly creates a random RFC 4122 version 4 UUID (also called a GUID). Click to generate more or copy the result. Generation runs locally in your browser, nothing is sent to a server, and it is free with no signup.

  1. Open the generator Load the UUID generator and a valid v4 UUID appears immediately.
  2. Generate more Click the generate button to produce a fresh random UUID, or set a count for several at once.
  3. Copy the result Click copy to put the UUID on your clipboard, ready to paste into your code or database.

About UUIDs

A UUID (Universally Unique Identifier) is a 128-bit number used to identify information in computer systems. UUIDs are standardized by RFC 4122 and are designed to be unique across both space and time.

Format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

Example: 550e8400-e29b-41d4-a716-446655440000

Frequently Asked Questions

A UUID (Universally Unique Identifier) is a 128-bit identifier that is practically guaranteed to be unique without requiring a central authority. It's used to identify objects, records, and entities in distributed systems.

UUID and GUID (Globally Unique Identifier) are essentially the same thing. GUID is Microsoft's term for UUID. They both refer to the same 128-bit unique identifier standard defined by RFC 4122.

While not mathematically guaranteed, the probability of generating duplicate UUIDs is astronomically low. With proper random number generation, you'd need to generate billions of UUIDs per second for years to have even a tiny chance of collision.

UUID version 4 uses random numbers for generation. This tool generates v4 UUIDs using cryptographically secure random number generation. The '4' in the third group indicates it's a version 4 UUID.

Use UUIDs for: distributed database primary keys, API request IDs, session identifiers, file names, cache keys, or any scenario where you need unique identifiers without a central coordination system.

UUIDs work well as primary keys in distributed systems and when you need to generate IDs client-side. However, they're larger than integers and can impact index performance. For simple applications, auto-increment integers may be more efficient.

You can remove dashes to get a 32-character hex string, but you cannot make UUIDs shorter without losing uniqueness guarantees. If you need shorter IDs, consider alternatives like nanoid, ULID, or custom base62/base64 encoding schemes.

UUIDs are typically displayed in lowercase, but they are not case-sensitive. "550e8400-e29b-41d4-a716-446655440000" and "550E8400-E29B-41D4-A716-446655440000" represent the same UUID. Most systems treat them as case-insensitive.

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