For UUIDv7 it isn't very clear on how the subsecond part is encoded. From the description of decoding it sounds like it would be multiplying the fraction of a s

For UUIDv7 it isn't very clear on how the subsecond part is encoded. From the description of decoding it sounds like it would be multiplying the fraction of a second by 2^n. but that isn't very explicit. And if you want to avoid floating point arithmetic you'll need to include a 10^p in there where p is how many digits of precision you have in base 10 (such as 3 for milliseconds)