The fastest way depends on what you already have

Most computers and phones come with a video editor that can slow down footage without installing anything new. Windows includes Photos, Mac has iMovie, and both iPhone and Android have built-in editors. If you want more control — like slowing only part of a video or adjusting the speed in smaller increments — you'll need a separate program. The trade-off is that free desktop editors are slower to learn but give you finer control, while phone apps are quicker but offer fewer options.

Slowing video down makes the file larger and takes longer to export, so budget extra time before you need the final file. Most free editors export at the same quality as the original, but some reduce resolution unless you pay for the full version.

Key Takeaways

  • Windows Photos and Mac iMovie both slow down video in three to five clicks without extra software.
  • Desktop editors like DaVinci Resolve (free) and Shotcut (free) let you slow different parts of the same video at different speeds.
  • Phone editors built into iOS and Android are the fastest option but usually only let you set one speed for the entire video.
  • Slowing video down makes the file larger and takes longer to export, so budget extra time before you need the final file.
  • Most free editors export at the same quality as the original, but some reduce resolution unless you pay for the full version.

Slowing down video on Windows using Photos

Open the Photos app (it comes with Windows 10 and 11), find the video file, and click it. At the top, click "Edit & Create" and then "Edit with Photos app." In the toolbar, look for the speed icon — it looks like a speedometer or gauge. Click it and you'll see options like 0.25x, 0.5x, 0.75x, and 1x (normal speed). Choose the speed you want and click "Save a copy." The app will export a new file with the slower speed applied to the entire video.

This method works for most common video formats (MP4, MOV, AVI) but can be slow if your video is longer than a few minutes. If Photos crashes or won't open your file, try a different editor. The exported file will be noticeably larger than the original because slow motion requires more data to play smoothly.

Slowing down video on Mac using iMovie

Open iMovie, create a new project, and drag your video into the timeline at the bottom. Right-click the video clip and select "Retime." A menu appears with speed options: you can choose preset speeds (0.25x, 0.5x, 0.75x) or drag a slider to set a custom speed. When you're done, click "Done" and then export the project by going to File > Share > File. Choose your resolution and click "Next" to save the file.

iMovie is straightforward but doesn't let you slow down just part of a video — the speed applies to the whole clip. If you need to slow only a section, you'll need to split the clip first by clicking where you want the split and pressing Command+B, then apply different speeds to each piece.

More control with free desktop editors: DaVinci Resolve and Shotcut

If you want to slow different parts of a video at different speeds, or adjust speed in smaller increments, download DaVinci Resolve (Windows and Mac) or Shotcut (Windows, Mac, and Linux). Both are free and don't require payment to export. In DaVinci Resolve, import your video, drag it to the timeline, right-click it, and select "Change Clip Speed." Type a percentage (50 for half speed, 25 for quarter speed) or use the slider. You can apply different speeds to different sections by splitting the clip first.

In Shotcut, right-click the video in the timeline and select "Properties," then adjust the "Speed" slider. Both programs take longer to learn than Photos or iMovie but give you frame-by-frame control and let you combine slow-motion sections with normal-speed sections in the same video. Export times are longer with these editors — a five-minute video slowed to half speed might take 10 to 20 minutes to export, depending on your computer's processor. Both programs export at the original quality by default, so you won't lose resolution.

Slowing down video on iPhone

Open the Photos app, find your video, and tap "Edit." Swipe left on the toolbar at the bottom until you see the speed icon (it looks like a gauge). Tap it and choose a speed: 0.25x, 0.5x, 0.75x, or 1x (normal). Tap "Done" and then "Save" to overwrite the original or "Save as New Clip" to keep both versions. The edited video stays in your Photos library.

iPhone's editor is the fastest option but only lets you set one speed for the entire video. If you need variable speeds, you'll need to use iMovie on your Mac or a third-party app like Adobe Premiere Rush (paid subscription) or CapCut (free, but includes watermarks unless you pay).

Slowing down video on Android

Open Google Photos, select your video, and tap the pencil icon to edit. Tap "Tools" at the bottom and then "Speed." Drag the slider left to slow down (0.25x to 0.75x) or right to speed up. Tap the checkmark to save. The edited version is saved as a new file in your Photos library.

If Google Photos doesn't have the speed tool (it varies by device and Android version), try the default Gallery app that came with your phone — most Android phones include a basic editor with speed controls. For more options, download CapCut (free) or Adobe Premiere Rush (subscription), both of which let you slow different sections at different speeds.

What happens to file size and export time

Slowing video down makes the file larger because the editor has to add extra frames to fill the gaps. A video slowed to half speed will roughly double in file size. A one-minute video at normal speed might be 50 MB; slowed to half speed, it could be 100 MB or more. This matters if you're uploading to social media or sending via email — slower videos take longer to upload.

Export time also increases. On a mid-range computer, a five-minute video slowed to half speed might take 15 to 30 minutes to export. On a phone, it's usually faster — five to ten minutes — because phones use hardware acceleration. If you're exporting on a laptop with limited RAM or an older processor, budget extra time and close other programs to speed things up.

Frequently Asked Questions

Can I slow down only part of a video?

Yes, but only with desktop editors like DaVinci Resolve or Shotcut. Split the video at the point where you want the speed to change, then apply different speeds to each section. Phone editors and Photos/iMovie apply the same speed to the entire video unless you split it into separate clips first.

Will slowing down video reduce the quality?

No, slowing video doesn't reduce quality if you export at the original resolution. The file gets larger, not worse. Some paid editors offer options to reduce quality to save space, but free editors keep the original quality by default.

What's the slowest speed I can use?

Most editors go down to 0.25x (one-quarter speed), which is four times slower than normal. Some desktop editors let you go slower, but the result looks choppy because there aren't enough original frames to fill the gaps. For very slow motion, you need video shot at a high frame rate (60fps or higher), not just slowed-down normal video.

Can I undo the slow-motion effect after I save?

If you saved over the original file, you'll need the original video file to undo it — the slow-motion version can't be sped back up without losing quality. Always save as a new file (most editors offer this option) so you keep the original. On phones, using "Save as New Clip" instead of overwriting protects your original.

Why does my video look stuttery after slowing it down?

This happens when the original video was shot at a low frame rate (24fps or 30fps). Slowing it down makes the gaps between frames more noticeable. To fix this, shoot at 60fps or higher if your camera supports it, or use an editor that can interpolate frames (add artificial frames between the real ones). DaVinci Resolve has this feature, but it's slower to export.