UUID Generator

What is UUID Generator?

A UUID generator produces RFC4122 Universally Unique Identifiers—128-bit values that are practically guaranteed to be unique across systems and time. UUIDs are widely used as database primary keys, API request IDs, distributed system identifiers, and session tokens. The tool supports two versions: v4 uses cryptographically secure random bits via crypto.getRandomValues or crypto.randomUUID; v7 embeds a Unix timestamp in milliseconds, making IDs sortable by creation time.

Real-world use cases include generating primary keys for new database records, creating unique filenames for uploads, assigning correlation IDs for distributed tracing, and generating secure tokens for temporary access. Because UUIDs are globally unique without coordination, they're ideal for distributed systems where multiple nodes create records independently. All generation runs entirely in your browser—no data is sent to any server.

How to Use UUID Generator

1. Set the Count (1–100) for how many UUIDs to generate at once.
2. Click Generate UUIDs or Generate 20 for a quick batch. A new set is generated each time.
3. Open Advanced to choose v4 Random or v7 Timestamp-sorted. Use v7 when you need IDs that sort chronologically (e.g. for database indexing).
4. Optionally set a Template (e.g. user-{uuid} or prefix-{uuid}-suffix) to wrap each UUID. The {uuid} placeholder is replaced with the generated value.
5. Toggle Uppercase or Remove hyphens for compatibility with systems that expect compact or uppercase IDs.
6. Click Copy to copy all generated UUIDs to your clipboard. Press Ctrl+Enter to generate, Ctrl+Shift+C to copy, or Esc to clear.

Tips & Best Practices

Use v4 when you need maximum randomness and don't care about sort order. Use v7 when you want IDs that sort by creation time (e.g. for time-series data or log ordering). Removing hyphens yields a 32-character hex string useful for URLs or compact storage. The template feature is handy for generating test data (e.g. order-{uuid}) or API payloads. Session Total tracks how many UUIDs you've generated in the current session. All randomness is cryptographically secure and suitable for production use.

When to Use This Tool

Use the UUID Generator when you need unique identifiers for database records, API keys, distributed system IDs, or temporary tokens. It's ideal for prototyping, test data generation, and one-off ID creation. For related tasks: use the Unix timestamp converter to inspect timestamps embedded in v7 UUIDs, the JWT decoder to inspect tokens that may contain UUIDs as claims, or the Regex tester to validate UUID format with patterns like [0-9a-f]{8}-[0-9a-f]{4}-....