UUID Generator
Generate RFC 4122 style UUID v4 or UUID v1 identifiers in your browser. Create one UUID or a batch, switch letter case, then copy or download the results for development, testing, databases, and API workflows.
Generated UUIDs
0 generated. Batch size is capped at 1000.
What Is a UUID Generator?
A UUID generator creates 128-bit identifiers that are commonly used as database keys, request IDs, file names, session references, event IDs, and test data. UUIDs are designed to be unique enough for distributed systems without requiring a central counter.
UUID v4 vs UUID v1
- UUID v4 is random-based and is the safest default when you need identifiers that do not reveal timing or machine details.
- UUID v1 is time-based and sorts roughly by creation time. This tool uses a random node value instead of exposing a real hardware MAC address.
- Both formats use the standard 8-4-4-4-12 UUID layout and set the version and variant bits correctly.
Common Uses
- Create primary keys or public IDs for prototypes and seed data.
- Generate correlation IDs for logs, traces, background jobs, and API requests.
- Prepare unique names for files, fixtures, messages, queues, and test records.
Developer Notes
UUIDs are useful, but they are not a substitute for every identifier strategy. Choose the version and storage format based on privacy, ordering, database indexing, and interoperability needs.
Client-side generation
UUIDs are generated locally in the browser. The generated list is not sent to a server by this tool.
Batch output
Generate up to 1,000 UUIDs at once, copy the full newline-separated list, or download it as a .txt file.
Case formatting
UUIDs are equivalent in lowercase or uppercase for most systems. Match the casing expected by your database, API, or codebase.
UUID Generator FAQ for Developers
Should I use UUID v4 or UUID v1?
Use UUID v4 for most applications because it is random-based and avoids exposing creation time or machine information. Use UUID v1 only when time ordering is useful and the privacy tradeoff is acceptable.
Are these UUIDs generated on the server?
No. This tool generates UUIDs in your browser, then uses browser clipboard and download APIs for copy and export actions.
Is UUID v4 unique enough for database IDs?
For typical distributed applications, UUID v4 has an extremely low collision probability when generated with a secure random source. You should still enforce uniqueness at the database layer when IDs are critical.
Can I use UUIDs as secrets or access tokens?
Do not treat a UUID as a secret by default. UUIDs are identifiers. For passwords, API keys, reset links, or bearer tokens, use purpose-built cryptographic token generation with enough entropy and proper expiration.
Why does UUID v1 include time information?
UUID v1 encodes a timestamp and clock sequence. Traditional UUID v1 can also include a machine node value; this browser tool uses a random node value to avoid exposing a real MAC address.