UUID → time
Extract the embedded timestamp from a UUID v1 (gregorian + MAC) or UUID v7 (unix millis). For v4, there's nothing to decode - it's pure entropy.
uuid
decoded
- version
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- variant
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- timestamp
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- unix millis
- -
- relative
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- node / random
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notes
v1 · 60-bit gregorian timestamp (100ns ticks since 1582-10-15) + clock-seq + 48-bit node id.
v4 · 122 bits of randomness - no time to extract.
v7 · 48-bit unix millis + 4-bit version + 12 random + 2-bit variant + 62 random.
v7 (RFC 9562, May 2024) is the recommended "sortable random" UUID. New code should prefer it.
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