Using UUIDs safely
What this generator produces
Choose a batch size and press Generate. Each line is a version 4 UUID, a 128-bit identifier with random bits and reserved version/variant bits. The browser’s Web Crypto generator supplies the randomness. Copy All copies the complete batch, one identifier per line; generating again replaces the displayed batch.
When to use one
Use these identifiers for test fixtures, public record identifiers, or importing sample records where a sequential number is inconvenient. A UUID such as 550e8400-e29b-41d4-a716-446655440000 illustrates the 8-4-4-4-12 hexadecimal format; do not reuse that example as a unique production identifier.
Limits and privacy
Random identifiers make accidental collisions very unlikely, but do not replace a database unique constraint. A UUID is not an authentication token, password or permission check. Output is generated locally and is not stored by this tool. Keep private identifiers out of public screenshots. A browser without Web Crypto shows an error instead of silently using weaker randomness.