How to Slow Down Video on iPhone

You can slow down an iPhone video by recording in Slo-mo or by reducing the speed of a clip you already have. The built-in Camera and Photos apps are enough for basic edits; exact controls vary slightly by iOS version and video type.

What You’ll Need

An iPhone with the video you want to slow down, or enough storage to record a new clip.
The Camera and Photos apps. For some advanced speed controls, use a video-editing app that supports changing clip speed.
For the smoothest slow motion, record the subject in good light and choose Slo-mo before filming.

Step-by-Step

Choose whether to record or edit. If you have not filmed the action yet, recording in Slo-mo generally gives a smoother result because the iPhone captures more frames per second. If you already have a normal-speed clip, try the Photos app first; it can adjust the slow-motion portion of supported Slo-mo recordings, but does not provide a general speed slider for every ordinary video.
Record a new Slo-mo clip. Open Camera and swipe through the available camera modes until Slo-mo is selected. Frame the subject, check that there is enough light, then tap the record button. Tap it again to stop. The recording is saved in Photos.
Review the recorded clip. Open Photos, find the Slo-mo video, and tap it to play. Check that the important action is within the slow-motion section. The phone may play the beginning and end at normal speed, with a slower section in the middle.
Adjust where the slow motion starts and ends. In Photos, open the Slo-mo clip and tap Edit. Look below the video preview for the timeline and its vertical speed markers. Drag the markers that define the slow-motion section to include the action you want slowed down. Preview the result, then tap Done to save.
Slow an existing regular-speed video. Open the clip in a video editor that offers a speed or playback-rate control. Add the clip to a project, select it on the timeline, open the speed control, and choose a rate below normal speed—for example, 0.5× is half speed. Preview the entire clip, then export or save a new copy. Controls and names differ between apps, so consult the app’s own instructions if the speed setting is not obvious.
Keep the original when possible. Before applying a permanent edit or replacing a file, make a duplicate or choose an option such as Save as New Clip if the editor offers it. This lets you compare versions and return to the original if the result looks choppy or the timing is wrong.
Check the saved video. Play the exported or edited version in Photos from beginning to end. Confirm that the slow section is where you intended, the audio is acceptable, and the video has finished exporting before sharing or deleting anything.

Common Mistakes

Expecting Photos to slow every video. Photos’ slow-motion timeline controls are for compatible Slo-mo clips. A regular video may need a separate editor with a speed adjustment.
Recording in normal mode and expecting Slo-mo detail. Slowing a standard clip makes its existing frames last longer; it cannot add the extra captured frames of a true Slo-mo recording. Fast movement may look jerky.
Dragging the wrong timeline markers. The markers set the boundaries of the slow section, not simply the clip’s start and end. Play the video after adjusting them to check the transition.
Using a very low speed without checking quality. The slower the clip, the more noticeable gaps between captured frames can be, particularly when the original was filmed at a normal frame rate.
Ignoring sound and export settings. Slowing video can lower or alter audio, and some editors mute or process sound automatically. Check audio and resolution settings before exporting.

Tips

For new footage, use the Camera app’s Slo-mo mode before recording rather than trying to create slow motion afterward.
Film in bright, even light. Shorter exposures in brighter conditions can make moving subjects look clearer; dim scenes often produce blur or image noise.
Keep the phone steady, or use a stable support. A slow-motion clip can make camera shake especially noticeable.
Record a little before and after the action. Extra footage gives you room to set the slow-motion section precisely.
Try a moderate reduction first, such as half speed, and compare it with the original. A subtle slowdown is often easier to watch than an extremely slow one.
Leave enough free storage for recording and exporting. A high-resolution video can take up considerably more space than a short text or photo file.

Troubleshooting

Slo-mo is not shown in Camera: Swipe across the camera modes, and check whether the Camera app is in a different capture mode. If it still is not available, restart the iPhone and install any iOS update offered in Settings. Available modes can differ by iPhone model.
The video plays entirely in slow motion or at normal speed: Open it in Photos, tap Edit, and inspect the Slo-mo timeline markers. Move them to set the intended section, preview, and tap Done. If there are no Slo-mo controls, it may be a regular video rather than a Slo-mo recording.
The slowed clip looks choppy: This is common when reducing the speed of footage recorded at a standard frame rate. Use a smaller slowdown, or record the action again in Slo-mo with good lighting. An editor’s frame interpolation may help in some cases, but can create visual artifacts.
The edit or export fails: Check available iPhone storage, close and reopen the editing app, and try exporting a shorter section. Keep the original clip until the finished file plays correctly.
The audio sounds odd or disappears: Check the editor’s audio and pitch options. Some tools preserve pitch, change it, or mute audio when changing speed. If the sound is important, preview it before saving and consider keeping the original audio separately.

Frequently Asked Questions

Can I slow down a video already recorded on my iPhone?

Yes. For a Slo-mo recording, adjust its slow-motion section in Photos. For a regular video, use a video editor that provides a speed control.

Can I slow down a video in the Photos app?

Photos can adjust the slow-motion portion of compatible Slo-mo clips. It does not offer a general speed slider for every ordinary video on all iOS versions.

How do I make only part of a video slow motion?

For a Slo-mo clip, use the timeline markers in Photos’ Edit view to set the slow section. In an editor, split or select the relevant portion and apply a lower speed to it.

Why does my slow-motion video look jerky?

The original may not contain enough frames for the selected slowdown. Record in Slo-mo for fast action, use good light, or reduce the amount of slowdown.

Can I change a slow-motion video back to normal speed?

For a Slo-mo clip edited in Photos, reopen Edit and move the markers so no section is slowed, if those controls are available. For an exported file, return to the original or adjust the speed in an editor.

Does slowing a video also slow its sound?

It can. Audio behavior depends on the app and its settings: sound may change pitch, be processed to preserve pitch, or be muted. Preview the result before sharing.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

More in this bed

The whole Tech How-To bed →