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UUID Generator
Generate random UUIDs (v4) and other UUID versions online. Create unique identifiers for databases and applications.
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About UUID v4
UUID v4 (Universally Unique Identifier version 4) is generated using random or pseudo-random numbers.
Format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
The "4" indicates version 4, and "y" is one of 8, 9, A, or B.
There are approximately 5.3 x 10^36 possible v4 UUIDs, making collisions practically impossible.
Key Features — UUID Generator
Generate UUID v1, v4, and v5
Bulk generation of multiple UUIDs
Choose with or without hyphens
Uppercase or lowercase output
Cryptographically secure random generation
Why Use This Tool — UUID Generator
Free Online Uuid generatorGuid generator — for EveryoneFast & Easy Unique id generatorUuid v4 — 100% FreeFree Online Random uuid
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Lightning Fast
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Works Everywhere
Use on any device — desktop, tablet, or phone. No downloads or plugins needed.
Frequently Asked Questions — UUID Generator
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier formatted as 32 hexadecimal digits separated by hyphens, like 550e8400-e29b-41d4-a716-446655440000. Version 4 UUIDs are randomly generated and the probability of collision is negligibly small, making them ideal for database primary keys and distributed systems.
What is the difference between UUID versions?
Version 1 uses the current timestamp and machine MAC address. Version 4 is entirely random and most commonly used. Version 5 generates a deterministic UUID from a namespace and name using SHA-1 hashing. Version 4 is recommended for most applications.
How unique are version 4 UUIDs?
Version 4 UUIDs have 122 random bits, giving approximately 5.3 x 10^36 possible values. The probability of generating two identical UUIDs is astronomically small. You would need to generate one billion UUIDs per second for 85 years to have a 50% chance of a single collision.