A playback speed calculator divides a video’s length by the speed you play it at. At 1.5x, a 1-hour lecture takes 40 minutes and saves you 20. At 2x it takes 30. Enter any length the way the player shows it to see it at each speed, the time you save, and how many days a long course takes.
How to work out a video’s length at a faster speed
Divide the length by the speed. A 1:23:45 lecture is 5,025 seconds, and 5,025 ÷ 1.5 is 3,350 seconds, or 55:50. The time you save is the original length minus the new one: 27:55. The calculator rounds to the nearest second, so the two always add up to the original.
Type the length the way the player shows it (1:23:45 or 45:00), as a number of minutes (90), or with units (1h 30m).
How long common lengths take at 1.25x to 2x
Each speed takes a fixed share off any length. 1.25x saves a fifth of the time, 1.5x saves a third, 1.75x saves three sevenths, and 2x saves half.
| Length | 1.25x | 1.5x | 1.75x | 2x |
|---|---|---|---|---|
| 10 minutes | 8:00 | 6:40 | 5:43 | 5:00 |
| 30 minutes | 24:00 | 20:00 | 17:09 | 15:00 |
| 40 minutes | 32:00 | 26:40 | 22:51 | 20:00 |
| 1 hour | 48:00 | 40:00 | 34:17 | 30:00 |
| 2 hours | 1:36:00 | 1:20:00 | 1:08:34 | 1:00:00 |
How many days a course takes
Enter the minutes you watch a day, and the calculator divides the length at your speed by that time. It rounds up, since a part day is still a day of watching. A 10-hour course at 1.5x is 6 hours 40 minutes. At 30 minutes a day, that’s 14 days: 13 full days and a short 14th.
The page address keeps the length, the speed, and the minutes a day, so you can bookmark the plan or send it to a study partner.
How to change the speed on YouTube
YouTube Help lists the steps for each device:
- On a computer: hover over the player, select Settings, then Speed, and choose a speed. With YouTube’s keyboard shortcuts,
>speeds the video up and<slows it down. - On a phone or tablet: tap the video, then Settings, then Playback speed.
- For a quick 2x: click and hold anywhere on the video, or tap and hold on a phone. It plays at 2x until you let go.
Open the same menu to go back to normal speed.
If the speed option is missing, YouTube Help names two limits: Android needs version 5.0 or above, and some smart TVs and streaming devices may not offer it. An embedded video on another site can also be stuck at normal speed, since YouTube’s player API lets an embed offer 1x only. Open the video on youtube.com for the full menu.
Can YouTube play faster than 2x?
Yes, with YouTube Premium. In January 2025, YouTube announced speeds up to 4x on mobile for Premium members. Premium’s auto speed, on the Android app and for videos in English, changes the speed as a video plays, so no calculator can predict it. For a fixed speed above 2x, enter it as a custom speed, up to 4x.
What to watch with the time you save
Watching faster frees up time, and a crowded home feed can take it straight back. Retube, our free Chrome extension, groups your subscriptions into feeds inside YouTube, such as Learning, Tech, or Cooking. You open a feed and see only the channels in it.
To set that up by hand or with Retube, read how to organize YouTube subscriptions. To watch one lecture without the sidebar and autoplay queue, use the cookie-free YouTube watcher.