Can you estimate playtime from replay folder size?
I've seen this question come up a few times on r/ssbm and while I've given hand-wavey answers before, I find myself in a good place to answer more rigorously now. We can break this question down to more basic ones: "how many bytes of replay data correspond to a single frame of gameplay?" and "how many bytes in the replay are unrelated to frames?". From there, we can estimate a duration by simply translating the 16.667ms per frame to minutes and seconds.