What slow motion video is and which tool to use

Slow motion video plays back footage at a slower speed than it was recorded, making fast action visible in detail. You create it by either recording at a high frame rate (more frames per second) and playing at normal speed, or by slowing down existing video in editing software.

The tool you choose depends on what you're starting with. If you're recording new footage on a smartphone, your phone's built-in camera app likely has a slow-motion mode. If you're working with video you already have, or if you want more control, you'll use video editing software on your computer — either free tools like DaVinci Resolve or CapCut, or paid software like Adobe Premiere Pro or Final Cut Pro.

The difference matters because recording in slow motion uses more storage (high frame rates create larger files), while editing existing video into slow motion is just a matter of changing playback speed — but the result won't look as smooth as footage shot at high frame rates.

Key Takeaways

  • Smartphones record slow-motion video through the camera app's slow-motion or slo-mo mode, usually at 120 or 240 frames per second, and save it as a normal video file you can share immediately.
  • Video editing software like DaVinci Resolve (free) or Adobe Premiere Pro (paid) lets you slow down any existing video, but the result depends on the original frame rate — footage shot at 24 or 30 fps will look choppier when slowed than footage shot at 60 fps or higher.
  • Recording at high frame rates uses significantly more storage space than normal video, so check your phone or camera's available space before recording long slow-motion clips.
  • Slow motion recorded on your phone can be edited further in the same apps (iMovie on iPhone, Google Photos on Android) or transferred to a computer for more detailed editing.

Recording slow motion on your phone

On iPhone, open the Camera app and swipe left until you see "Slo-Mo" listed at the bottom. Tap it, then record as you normally would. The phone captures at either 120 fps or 240 fps depending on your model and lighting. When you stop recording, the video is saved to your Photos app and plays back at slow speed automatically.

On Android, the process varies by manufacturer. In Google's native Camera app, tap the menu icon (three horizontal lines) and select "More" or "Video," then look for "Slow Motion" or "Slo-Mo." Samsung phones have a dedicated slow-motion mode in their Camera app. Once recorded, the video appears in your gallery as a normal file.

One important detail: slow-motion video files are much larger than regular video because they contain more frames. A 10-second slow-motion clip at 240 fps can use 200 MB or more, depending on resolution. Check that you have space before recording, especially if you're recording multiple clips.

Slowing down existing video in editing software

If you have video you want to slow down, you'll import it into editing software. DaVinci Resolve is free and works on Windows, Mac, and Linux. Adobe Premiere Pro costs $22.49 per month and works on Windows and Mac. Final Cut Pro costs $300 once and works only on Mac. All three let you adjust playback speed.

In DaVinci Resolve, import your video by dragging it into the Media Pool on the left. Drag the clip into the timeline at the bottom. Right-click the clip and select "Change Clip Speed." A dialog opens where you can enter a percentage — 50% plays at half speed, 25% at one-quarter speed. Click "Change" and the clip slows down in the timeline.

In Adobe Premiere Pro, drag your video into the timeline, right-click it, and select "Speed/Duration." Enter a new duration (making it longer slows playback) or a percentage of original speed. In Final Cut Pro, select the clip in the timeline, press Command+D, and adjust the retime slider that appears.

The result depends on your source footage's frame rate. Video shot at 24 or 30 fps will look choppy when slowed significantly because the software has to repeat frames to fill the gaps. Video shot at 60 fps or higher looks smoother because there are more frames to work with.

Understanding frame rate and why it matters

Frame rate is how many still images (frames) are captured per second. Standard video is 24, 25, or 30 fps. High frame rate video is 60 fps or higher. When you slow down video, the software stretches the time between frames, and if there aren't many frames to begin with, you see stuttering.

If you record at 120 fps and slow it to half speed (60 fps playback), you have plenty of frames and the motion looks fluid. If you record at 30 fps and slow it to half speed, the software has to guess what happened between frames, and the result looks jerky. This is why slow-motion mode on phones records at 120 or 240 fps — it gives you enough frames to slow down without losing smoothness.

When you're deciding whether to record in slow motion or edit it later, remember: you can't add frames that weren't recorded. If you think you might want slow motion, record at the highest frame rate available, even if you don't use it. You can always play normal-speed video at normal speed, but you can't make choppy video smooth.

Exporting and sharing your slow-motion video

On your phone, slow-motion video recorded in the camera app is ready to share immediately. Open Photos, select the clip, and tap Share to send it via text, email, or social media. The video keeps its slow-motion playback on any device that receives it.

If you edited the video in DaVinci Resolve, Adobe Premiere Pro, or Final Cut Pro, you need to export it before sharing. In DaVinci Resolve, go to the Deliver tab at the top right, choose a format (H.264 is standard for most uses), and click "Render All." The software creates a new video file on your computer. In Adobe Premiere Pro, go to File > Export > Media. In Final Cut Pro, go to File > Share and choose your destination.

For social media, export at 1080p resolution and H.264 format — this works on all platforms and keeps file size reasonable. If you're sharing via email or messaging, consider exporting at a lower bitrate to reduce file size, though this reduces quality slightly. Most platforms (YouTube, TikTok, Instagram) accept slow-motion video at any frame rate, though they may re-encode it during upload.

Common problems and how to fix them

Slow-motion video looks choppy or stutters. This usually means the source footage has a low frame rate. If you recorded it yourself, re-record at the highest frame rate available. If you're editing existing video, there's no fix — you can only slow it down as much as the frame rate allows. Some editing software has "optical flow" or "frame interpolation" features that try to create new frames, but these produce mixed results and can look unnatural.

The video is too large to send or upload. Slow-motion files are bigger because they have more frames. Export at a lower bitrate (try 8 Mbps instead of 15 Mbps) or lower resolution (720p instead of 1080p). You lose some quality, but the file shrinks significantly. Alternatively, upload to a cloud service like Google Drive or Dropbox and share a link instead of sending the file directly.

Audio sounds wrong or is out of sync. When you slow down video, audio slows down too, which makes voices sound deeper and speech harder to understand. If you're slowing video significantly, consider removing the original audio and adding music or narration instead. In editing software, select the audio track and delete it, then import new audio.

When to record slow motion versus edit it later

Record in slow motion if you know you want the effect and your phone or camera supports it. You get the smoothest result because you're capturing at high frame rates. The tradeoff is storage space — slow-motion files are large.

Edit video into slow motion later if you're not sure whether you'll need it, or if you're working with footage that's already been recorded. This gives you flexibility, but the result depends on the original frame rate. If the original video was shot at 24 or 30 fps, slowing it down will look noticeably choppy.

For action that happens very quickly — a ball bouncing, water splashing, a person jumping — record in slow motion if possible. For slower action or talking, editing existing video is usually fine because the lower frame rate is less noticeable.

Frequently Asked Questions

Can I slow down a video that was recorded at normal speed?

Yes, any editing software can slow down any video. The result depends on the original frame rate. Video shot at 60 fps or higher will look smooth when slowed. Video shot at 24 or 30 fps will look choppy because there aren't enough frames to fill the gaps smoothly.

Does slow-motion video work on all phones?

Most modern smartphones have slow-motion recording built into the camera app. iPhones have had it since the iPhone 5S. Most Android phones made in the last five years have it. Check your camera app's menu to see if "Slo-Mo" or "Slow Motion" is listed as an option.

How much storage does slow-motion video use?

A 10-second slow-motion clip at 240 fps typically uses 150 to 300 MB depending on resolution and lighting. Normal video at 30 fps uses about 30 to 50 MB for the same length. Check your phone's available storage before recording long slow-motion clips.

Can I speed up slow-motion video back to normal?

Yes. In editing software, select the clip and change the speed to 200% (or 400% if it was recorded at 240 fps). The video plays at normal speed but with more frames, which can look smoother than the original if it was shot at low frame rate.

What's the difference between slow motion and time lapse?

Slow motion plays recorded video at a slower speed, making fast action visible in detail. Time lapse records at a slower frame rate (one frame every few seconds) and plays at normal speed, compressing long periods into seconds. They're opposite effects created in opposite ways.