How do I make a slow-motion video on a Mac?

Use Crisp's Speed lane. Pick 0.5× or 0.25×, drop your clip in, and it retimes the video and pitch-corrects the audio on-device. Export is works entirely offline.

Does slowing a video down make it look choppy?

Slowing below the source frame rate repeats frames, which can look slightly stuttery. For buttery slow motion, run Crisp's Enhance lane with Smooth motion first — it interpolates extra frames — then slow the clip down.

Can I make a slow-mo video for free no subscription?

Yes. Crisp's Speed lane is in the free tier and never adds a watermark. Everything runs on your Mac, so nothing is uploaded.

Can Crisp also speed a video up?

Yes — the same Speed lane does 2× (fast) and 4× (timelapse) as well as 0.5× and 0.25× slow motion, with the audio kept in tune.

Guide · How to slow-mo a video on Mac

How to slow down a video on a Mac

Want a dramatic slow-motion clip from footage you already shot? Here's how to slow a video down on a Mac in about a minute — 0.5× or 0.25×, with the audio kept in tune, entirely offline.

Updated July 2026 · step-by-step

The short version

Open Crisp → Speed

Grab the free Crisp app for Mac and open it. Click the Speed tab in the Tools panel.
Pick a slow-mo speed

0.5× plays at half speed (twice as long); 0.25× is super slow-mo (four times as long). Fast-forward and timelapse (2× / 4×) are right there too.
Drop in your clip

Drag your video onto the window. Crisp retimes it and pitch-corrects the audio, so slowed-down voices don't drop into a deep drone.
Export

Crisp renders the slow-motion clip on your Mac and saves it beside the original — one-time.

Want buttery-smooth slow motion?

Slowing a clip below its native frame rate repeats frames, which can look a touch stuttery. For silky slow motion, first run Enhance with Smooth motion on, Crisp interpolates extra frames to a higher frame rate, then switch to Speed and slow it down. Two on-device passes, still offline.

Speeds at a glance

Speed	Effect
0.25×	Super slow-mo · 4× longer
0.5×	Slow motion · 2× longer
2×	Fast · half the length
4×	Timelapse · quarter the length

Why do it on-device?

Private & offline. Your footage never leaves your Mac — no upload, no cloud.
No account, no subscription. Free to try; own it once.
Audio stays in tune. Crisp pitch-corrects, so slow-mo speech sounds natural.

Make your first slow-mo clip free

Free to try on your Mac. No account, no subscription — nothing leaves your device.

Download Crisp for Mac

Apple Silicon · macOS 12+ · Notarized

Slow motion questions

How do I slow down a video on a Mac?

Open Crisp, choose the Speed lane, pick 0.5× or 0.25×, and drop your clip in. It retimes the video and pitch-corrects the audio on-device.

Is it free?

Yes — the Speed lane is in the free tier. Free exports carry a small “Made with Crisp” mark; a one-time $129 removes it.

Why slow motion looks bad when the footage wasn't shot for it

A clip recorded at 30fps and slowed to a quarter speed has to show four times as many frames as were captured. Something has to fill the gap. The cheap answer is to hold each frame longer, which is what makes slowed footage look juddery rather than smooth.

This is why footage shot at 120 or 240fps slows beautifully and normal 30fps footage doesn't. If you know in advance that a shot will be slowed, record it at the highest frame rate your camera offers — an iPhone will do 240fps at 1080p, and that's four seconds of usable slow motion for every second you shoot.

Getting the audio right

Slowed audio drops in pitch and usually sounds wrong. For most slow-motion shots the cleanest choice is to mute the clip and let music or the surrounding scene's audio carry it. Mute the slowed clip rather than trying to correct the pitch.

How slow is too slow

Half speed reads as deliberate and almost always works. Quarter speed is where 30fps footage starts to fall apart unless the shot is very steady. Below that you need high-frame-rate source or the result looks like a stutter rather than an effect.

Background: how frame interpolation works.