Work out video length at playback speed instantly with clear inputs, formula shown and shareable results.
Playback speed divides the runtime, and skipping intros removes time before the division applies. Combining both gives an effective speed above the nominal setting — 1.75x plus a four minute skip on a 78 minute video works out to nearly 1.86x overall.
Playback time
time = (length - skipped) / speed; effective speed = original length / time taken
1.5x suits most recorded lectures, and 2x works for familiar material. Dialogue-heavy drama becomes unpleasant much sooner.
Modern time-stretching preserves pitch, which is why 1.5x is far more listenable now than the chipmunk effect of older players.