UUID Generator

Need a UUID for a database key, API token, or test fixture? Generate v4 UUIDs one at a time or in bulk — up to 100 at once — and copy them straight to your clipboard.

What is UUID Generator?

A UUID Generator creates random Version 4 UUIDs that are universally unique identifiers. Each UUID follows the standard format 8-4-4-4-12 (36 characters with hyphens). Generate 1 to 100 UUIDs at once for any application.

Formula

UUID v4 format: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

Where x is a random hex digit and y is one of 8, 9, A, or B (RFC 4122 variant).

Total combinations: ~5.3 × 10^36

How to Calculate

Choose how many UUIDs to generate (1-100).
Click the Generate UUID button.
Copy individual UUIDs or use Copy All.
Toggle auto-copy to auto-copy on generation.

Example

Generated UUID: 550e8400-e29b-41d4-a716-446655440000 — a standard v4 UUID with the 4 in position 13 indicating version 4, and "a" in position 17 indicating the RFC 4122 variant.

Key Benefits

Generate 1-100 UUIDs instantly
Copy with one click
Auto-copy option for workflow efficiency
Free no sign-up required

Common Mistakes to Avoid

Using sequential IDs instead of UUIDs for distributed systems
Assuming UUIDs are sortable by time (use UUID v7 for time-sortable)
Storing UUIDs as strings instead of binary for performance

Pro Tips

Use UUID v4 for general-purpose unique IDs
Store UUIDs as binary(16) in databases for performance
Use UUID v7 if time-ordered sorting is needed
Never generate UUIDs client-side for security-critical applications

Key Terms Explained

UUID: Universally Unique Identifier
UUID v4: Random version 4 UUID
GUID: Microsoft term for UUID
RFC 4122: UUID standardization document

Common Use Cases

Database primary keys for distributed systems
API resource identifiers
User session tokens
Order and transaction IDs

Frequently Asked Questions

What is a UUID?

UUID (Universally Unique Identifier) is a 128-bit identifier standardized by RFC 4122. Version 4 UUIDs are randomly generated and practically guaranteed to be unique across systems.

How unique are UUIDs?

Extremely unique. There are 5.3×10^36 possible v4 UUIDs. The probability of collision is so low that you could generate 1 billion UUIDs per second for 100 years and still have near-zero collision risk.

What are UUIDs used for?

UUIDs are used as database primary keys, API resource identifiers, session tokens, transaction IDs, and anywhere unique identifiers are needed without a central authority.

What is the difference between UUID and GUID?

GUID (Globally Unique Identifier) is Microsoft's implementation of the UUID standard. They are functionally identical and interchangeable.

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