Tiny Online Tools
Decode the Time Hidden Inside a UUID
Not every UUID is random. Some versions encode the exact moment they were created:
- v1 — 60-bit clock in 100-nanosecond intervals since 1582-10-15 (RFC 4122).
- v6 — same clock as v1, rearranged so that lexicographic sort equals creation order.
- v7 — 48-bit millisecond Unix timestamp + random payload; the new RFC 9562 standard for time-sortable IDs.
- v4 and v5 — no timestamp. v4 is purely random; v5 is a hash of a namespace + name.
The UUID Timestamp Extractor detects the version, reads the embedded clock, and shows you the creation time in ISO 8601, your local timezone, and Unix milliseconds.
Why It's Useful
- Debugging — find out when a log record, database row, or API request was really created.
- Forensics — correlate UUIDs with other time-stamped evidence.
- Security testing — verify that an application isn't leaking creation times via v1 UUIDs when uniqueness was the only requirement.
- Ordering check — confirm v7 IDs are actually sorting chronologically.
Notes
- v1 also embeds a 48-bit node (MAC address) field. The tool does not surface it by default to avoid encouraging deanonymization, but the information is still present in the raw UUID.
- v7 has 1 ms resolution. v1 and v6 have 100 ns resolution but in practice the low bits reflect a clock-seq counter, not sub-millisecond precision.
- The tool runs fully client-side; no UUID ever leaves your browser.