Playback Speed Guide: Length at 1.25x, 1.5x and 2x

Divide the original duration by the playback speed. A 90-minute lecture at 1.5x takes 60 minutes because 90 divided by 1.5 equals 60. Speed changes playback time; it does not remove any part of the recording.

The playback-speed formula

Divide the original duration by the playback speed. A 90-minute lecture at 1.5x takes 60 minutes because 90 divided by 1.5 equals 60. Speed changes playback time; it does not remove any part of the recording.

Common speeds and time saved

At 1.25x you save 20% of the original time; at 1.5x you save one third; at 2x you save half.

Choosing a useful speed

Speech clarity depends on the speaker, subject and listener. Try 1.25x for dense explanations, then increase gradually. Slow down for names, formulas or unfamiliar accents instead of treating the maximum speed as the goal.

Working with hours and minutes

Convert the full duration to seconds, divide once, then convert the answer back. This avoids mistakes such as dividing the hour but forgetting the remaining minutes. Round only the final display.

Planning a playlist or study session

Calculate each item at its intended speed and add the adjusted durations. Do not average speed settings: a short clip at 2x and a long lecture at 1.25x are weighted differently. Include pauses for notes, exercises or advertisements when scheduling real study time.

Some players preserve pitch while changing speed; specialized software may not. Treat the calculated duration as exact playback time and the planned session as a practical estimate.