Playback Speed Calculator

The division. Time at the new speed is the 1× length divided by the speed. Faster than 1 shortens the sitting. Slower than 1 lengthens it. 90 ÷ 1.5 is 60 exactly, so the seconds line is 0. 45 ÷ 2 is 22.5, and 0.5 of a minute is 30 seconds, so the about-line says 22 minutes 30 seconds. The decimal is rounded to three places. The seconds are rounded to the nearest second from the leftover fraction. A speed of 0.25 quadruples the sitting. A speed of 4 cuts it to a quarter. Speeds outside that range are refused so a typo of 15 does not pretend to be a player setting.

What is not included. Ads, credits you skip, and a player that rounds differently are not in the number. The formula line states the division and repeats the 90-at-1.5 example so a screenshot carries the rule. This is not the time calculator, which adds and subtracts durations. This page only scales one duration by a rate.

Units. Minutes in, minutes out. If you have seconds, divide by 60 before you type, or multiply the result by 60 after. The about-line is the only place seconds appear, and they are the fractional minute, not a separate input.

Write the 1× length from the file, not from memory of a broadcast with adverts. A 44 minute episode and a 45 minute episode diverge once you divide. Press Calculate after you change either box. The form does not update as you type, so a half-edited speed does not flash a wrong sitting time. Keep the speed inside the range the player actually offers.

A lecture recorded at 50 minutes and played at 1.25 is not one of the samples, but the same division applies: type 50 and 1.25 and read the result rather than guessing. Players sometimes show remaining time instead of total time. This page always uses the full length you type. If you have already watched ten minutes, subtract first, using the time calculator, and then scale what is left. Doing both steps in your head is how 1.5× gets applied to the wrong number. The seconds rounding can disagree with a player that truncates. A difference of one second on a long film is the rounding, not a second hidden feature. Speeds such as 1.25 and 1.75 are allowed because they sit inside 0.25 and 4. A speed of 1 returns the length unchanged, which is a useful sanity check before you trust a stranger speed.

Write the speed as a decimal, not as a percent. 1.5 is one and a half times, not 1.5 percent. A player labelled 150 percent is the same rate only after you convert. This page will not do that conversion. Type 1.5. The minutes you type should be the file duration from the player’s own info panel. A rounded “about an hour and a half” is 90 if you decide it is, and 100 if you decide otherwise. The tool cannot hear which you meant.

A 90 minute film at 1.5×

Inputs: Length: 90 | Speed: 1.5

Leave the length at 90 and the speed at 1.5, then press Calculate. Playback is 60 minutes.

Result: Length at 1x: 90 minutes Speed: 1.5x Playback: 60 minutes About: 60 minutes 0 seconds Time = length ÷ speed. A 90 minute film at 1.5x is 60 minutes.

A 45 minute episode at 2×

Inputs: Length: 45 | Speed: 2

Set the length to 45 and the speed to 2, then press Calculate. Playback is 22.5 minutes.

Result: Length at 1x: 45 minutes Speed: 2x Playback: 22.5 minutes About: 22 minutes 30 seconds Time = length ÷ speed. A 90 minute film at 1.5x is 60 minutes.

Why is 90 minutes at 1.5× equal to 60?

Because 90 divided by 1.5 is 60. Faster playback shortens the sitting.

What does the about-line do with 22.5?

It splits the fraction into seconds. Half a minute is 30 seconds, so you see 22 minutes 30 seconds.

Can the speed be 0.5?

Yes. Between 0.25 and 4. Half speed doubles the sitting.

Are ads included?

No. Only the length you type is divided.

Does it add two durations?

No. The time calculator does that. This page only scales one length.

Is the video uploaded?

No video is involved. The division runs in the browser.