iPhone 16 Slow Motion Video Not Working? Fix It

If your iPhone 16’s slow-motion video isn’t working, the most common cause is that you’re recording in the wrong mode or your camera settings are misconfigured. This guide walks you through the exact steps to get Slo‑mo recording back, explains why it fails, and answers the questions people actually ask.

Why Slow Motion Stops Working

The iPhone 16’s Slo‑mo mode records at 120 or 240 frames per second (fps) and then plays them back at 30 fps, creating that dramatic slow effect. When it “isn’t working,” the problem usually falls into one of four buckets:

You’re in the wrong camera mode – Slo‑mo is a separate mode in the Camera app, not a toggle inside Video mode.
The frame rate is set too low – If you’ve changed the Slo‑mo setting to 120 fps, the effect is less pronounced than 240 fps.
Low light is forcing the camera to drop fps – In dim scenes, the iPhone may automatically reduce the frame rate to keep the video bright enough, which makes slow motion look like normal video.
You’re viewing the video incorrectly – The slow-motion portion only plays in the section you’ve marked with the vertical white lines in the Photos app; the rest plays at normal speed.

Quick Fix: Check Your Camera Mode

Open the Camera app.
Swipe left on the mode carousel (the strip above the shutter button) until you see Slo‑mo.
If you don’t see it, tap the chevron (^) at the top center of the screen to reveal all modes, then tap Slo‑mo.
Press the red record button. You’ll see a small timer showing the frame rate (e.g., 120 fps or 240 fps) at the top of the screen.
Record for at least 3–5 seconds, then stop.

If you were in Video mode, this is almost certainly the issue. Slo‑mo is a distinct mode, and recording in Video will always give you normal-speed footage.

Check Your Slo‑mo Settings

Your iPhone 16 lets you choose between 120 fps and 240 fps. The higher the fps, the slower the motion, but 240 fps requires more light. To check or change it:

Go to Settings > Camera > Record Slo‑mo.
Choose 1080p at 120 fps or 1080p at 240 fps. (The 4K option is available on Pro models but still uses 120 fps.)
If you’re in a dim room, switch to 120 fps – it will look smoother and brighter, though the slow-motion effect will be less dramatic.

If you had previously set it to 120 fps and expected 240 fps, that’s why the effect seems weak. Try 240 fps outdoors or in bright light.

How to Play Back Slow Motion Correctly

Even after recording correctly, you might think it’s broken because the video plays at normal speed. Here’s the trick:

Open the video in the Photos app.
Tap Edit in the top right.
You’ll see two vertical white lines at the bottom of the timeline. These mark the start and end of the slow-motion section.
Drag the left line to where you want the slow motion to start, and the right line to where it should end.
Tap Done.

By default, the slow-motion effect applies only to the middle portion of the clip. If you don’t adjust the lines, the beginning and end will play at normal speed, which can make the whole thing feel like it’s not working.

Low Light and Frame Rate Drops

The iPhone 16’s camera automatically adjusts frame rate based on available light. In dark environments, the camera may drop from 240 fps to 120 fps, or even to 30 fps, to let in more light. This is not a bug – it’s a physical limitation of the sensor.

If you’re trying to record slow motion indoors, you’ll get better results by:

Turning on more lights.
Moving closer to a window or light source.
Switching to 120 fps in Settings to avoid the automatic drop.

There’s no manual override for this on the iPhone 16 – the camera decides. If you need slow motion in low light consistently, consider a third-party app that lets you lock exposure, but even then, the sensor can only capture so much light.

Other Common Causes and Fixes

Storage full – Slo‑mo videos are large (about 350 MB per minute at 240 fps). If your iPhone is low on space, the camera may refuse to record. Check Settings > General > iPhone Storage and free up space.
Camera app glitch – Force-close the Camera app (swipe up from the bottom and hold, then swipe the Camera app away) and reopen it.
iOS bug – Restart your iPhone by holding the side button and either volume button until the power off slider appears, then slide to power off and turn it back on.
Settings reset – Go to Settings > General > Transfer or Reset iPhone > Reset > Reset All Settings. This won’t delete your data, but it will reset camera preferences to defaults.

Frequently Asked Questions

Why is my iPhone 16 slow motion video playing at normal speed?

Most likely the slow-motion effect is only applied to a portion of the clip, or the clip was recorded in Video mode. Open the video in Photos, tap Edit, and adjust the white vertical lines to cover the section you want slowed down. If the whole clip is normal speed, check that you were in Slo‑mo mode and that your frame rate setting is 120 or 240 fps.

Does iPhone 16 have 240 fps slow motion?

Yes, the iPhone 16 and iPhone 16 Pro support 1080p at 240 fps. You can set this in Settings > Camera > Record Slo‑mo. Note that 240 fps requires bright light; in dim conditions the camera may automatically drop to 120 fps.

Why is my slow motion blurry on iPhone 16?

Blurriness usually comes from low light forcing a slower shutter speed, or from moving the phone too quickly while recording. Try recording in brighter conditions, keep the phone steady, and make sure the lens is clean. Also, 240 fps captures more frames per second, so any shake becomes more noticeable.

Can I change the slow motion effect after recording?

Yes. In the Photos app, open the Slo‑mo video, tap Edit, and drag the white vertical lines to change which parts are slowed down. You can also adjust the speed of the slow-motion section by dragging the small dots at the top of the timeline, but you cannot change the frame rate after recording.

Why does my iPhone 16 slow motion stop recording after a few seconds?

This happens when storage is nearly full or when the phone overheats. Slo‑mo videos are large, and the iPhone may stop recording to prevent data loss. Check your available storage and let the phone cool down if it feels warm.

Is there a way to record slow motion with the front camera?

No, the front (TrueDepth) camera on the iPhone 16 does not support Slo‑mo mode. You can only use Slo‑mo with the rear camera. For the front camera, you can use the standard Video mode and then apply a slow-motion effect in a third-party editing app, but the result won’t be as smooth.

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

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