UUID v1 Generator
Generate a mock time-based UUID v1 string instantly — timestamp-style identifiers for testing and demos. Free, client-side UUID v1 generator.
🔒 100% Client-Side Processing
Your data is processed entirely in your browser and never transmitted to any server.
Common Use Cases
Testing time-ordered ID handling
Produce v1-format identifiers to verify systems that parse or sort by UUID version and timestamp fields.
Fixture variety
Mix v1-style IDs into test data for code that must accept multiple UUID versions.
Frequently Asked Questions
- How does UUID v1 differ from v4?
- v1 encodes a timestamp and traditionally a MAC address, making IDs sortable by creation time but potentially privacy-leaking; v4 is pure randomness. This tool creates a v1-formatted mock using the current time plus random bits.
- Why "mock" — is it not a real UUID v1?
- It follows the v1 layout (time fields and version bits) but fills the node segment with random data instead of a real MAC address — correct for testing formats and parsers, while leaking nothing about your hardware.
- Can I read a real timestamp out of these?
- No. A genuine UUID v1 encodes the moment it was created and the generating node, and these values only imitate that layout — the time and node fields are random rather than meaningful. Anything that parses the embedded timestamp will read nonsense, which is exactly why they are safe as test fixtures.
- When is v1 genuinely preferable to v4?
- When identifiers become a database index. Because v1 values share a time-ordered prefix, consecutive inserts land near each other in a B-tree, whereas fully random v4 keys scatter writes across the index and fragment it. That locality is also the privacy cost — a real v1 leaks creation time and host.
- What should I use for identifiers in production?
- Use the UUID Generator, which produces proper random v4 values suitable for real records. Reserve these mock v1 values for fixtures and tests where you need something that merely looks like a v1 without carrying real timing information.
- Is my data private when I use this tool?
- Yes. This tool runs entirely in your browser using client-side JavaScript — nothing you type is transmitted to, logged by, or stored on any server. You can safely process confidential text, tokens, or code.