UUID Generator creates cryptographically random UUID v4 identifiers using your browser's secure random number generator. UUIDs are 128-bit unique identifiers used for database primary keys, API tokens, session IDs, and anywhere you need globally unique values.
How to use this tool
Enter how many UUIDs you want (default 5, max 50).
Click Generate to create them instantly.
Each UUID is displayed with an individual Copy button.
Use them for database IDs, API keys, file names, or tracking codes.
Generate more anytime — collision probability is astronomically low.
Frequently asked questions
What is a UUID?
A Universally Unique Identifier — a 128-bit value formatted as 32 hex digits in 5 groups (e.g., 550e8400-e29b-41d4-a716-446655440000). Version 4 UUIDs are randomly generated.
Can two UUIDs ever be the same?
Theoretically possible but practically impossible. UUID v4 has 122 random bits — the probability of collision is 1 in 2.71×10^18. You'd need to generate 1 billion UUIDs per second for 86 years to have a 50% chance of one duplicate.
UUID vs auto-increment ID — which is better?
Auto-increment is simpler and more efficient for single-database systems. UUIDs are better for distributed systems, APIs, and when you don't want sequential/predictable IDs. UUIDs are larger (16 bytes vs 4-8 bytes).
What's the difference between UUID versions?
v1 uses timestamp + MAC address (can leak info). v4 is pure random (most common). v5 is deterministic from a name/namespace. v7 is newer — time-ordered for better database indexing while still being unique.