UUID Generator
Generate cryptographically secure UUID v4 with one click.
Set the number of UUIDs to generate (1-100) and click "Generate". Toggle "Uppercase" to switch between upper and lowercase. Toggle "No hyphens" to remove hyphens. Click "Copy All" to copy the generated UUIDs to your clipboard.
What is UUID?
UUID (Universally Unique Identifier) is a 128-bit unique identifier. It is widely used in distributed systems to generate unique IDs without central management. UUID v4 is randomly generated with extremely low collision probability, making it suitable for database primary keys, session IDs, API keys, and more.
What is UUID?
UUID v4 is represented in the format xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx. The "4" indicates version 4, and "y" is one of 8, 9, a, or b. It consists of 36 characters total (including hyphens). This tool uses a cryptographically secure random number generator (crypto.getRandomValues).
UUID v4 Format
Q. Are the generated UUIDs truly unique?
A. UUID v4 uses 122 bits of random values, so the theoretical collision probability is extremely low (less than 50% even after generating approximately 2^61 UUIDs). They can be considered unique for practical purposes.
Q. Is my data secure?
A. All generation processing is completed within your browser. Generated UUIDs are never sent to any server. A cryptographically secure random number generator is used.