What is UUID version 4?

UUID v4 is a 128-bit identifier generated using random or pseudo-random numbers. Out of 128 bits, 122 bits are purely random, giving 5.3 × 10^36 possible unique values.

Can two UUID v4 values collide?

The probability of a collision is astronomically low. You would need to generate approximately 1 billion UUIDs every second for about 85 years to have a 50% chance of generating a single duplicate.

UUID Generator — Free Online RFC 4122 Version 4 UUID / GUID Maker

How to Use the UUID Generator

Select Batch Quantity

Choose how many UUIDs to generate (from 1 up to 50 at once).

Click Generate

Click "Generate UUID" to produce new random identifiers.

Copy to Clipboard

Copy individual UUIDs or all generated IDs at once.

UUID v4 Format Specification (RFC 4122)

A canonical UUID v4 string consists of 32 hexadecimal digits displayed in 5 groups separated by hyphens.

xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

Where 4 represents the version number (Version 4: random), and y indicates variant bits (8, 9, a, or b).

Why Choose Our UUID Generator?

Cryptographically secure via window.crypto.randomUUID()

RFC 4122 v4 compliance

Bulk generation up to 50 UUIDs

Uppercase and lowercase format support

Pro Tips for Best Results

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Frequently Asked Questions

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