How to remove background noise from a video on a Mac
A great clip with a hissy, humming, air-conditioner-in-the-background soundtrack is a shame. You don't need a DAW to fix it. Here's how to remove background noise from a video on a Mac in one tap, 100% offline: the picture is untouched, and there's no account, no upload, no watermark.
The fastest way: just ask
Crisp has a plain-English box ("Or just tell Crisp what to do…"). Drop your video in and type it:
- reduce the background noise — clean up the audio
- remove the hiss — knock down constant hiss
- get rid of the hum — clear an electrical/AC hum
- clean up the audio — general noise reduction
Crisp reads the request, switches to the Audio lane's Denoise mode, and you just press the button.
Step by step: the Audio lane
-
Open Crisp and drop in your video
Get the free Crisp app for Mac and drag your clip onto the window. Nothing is uploaded — the whole job runs on your Mac.
-
Pick the Audio lane, then Denoise
Choose Audio in the task row and switch the mode to Denoise.
-
Press it
Crisp runs a noise reducer over the audio and clears low-end rumble on-device. The picture is stream-copied untouched — only the audio is cleaned.
-
Save
The cleaned clip lands beside your original — watermark-free, with the video never re-rendered.
Great for constant noise — gentle on voices
Denoise targets the steady stuff: tape hiss, an electrical hum, an AC unit or fan, low-end rumble. It's tuned conservatively so speech and music stay natural rather than getting that underwater, over-processed sound. It won't erase a one-off door slam or a passing car — but a constant noise floor drops noticeably. Want the levels even too? Run Normalize after.
Audio noise vs video noise
Two different "noise" problems, two different tools:
- Background noise in the sound — hiss, hum, AC drone. That's this guide: the Audio lane's Denoise mode.
- Visual noise / grain in the picture — speckle in dark or low-light footage. For that, use Enhance / Low-light instead.
Crisp vs iMovie vs online noise removers
| Crisp | iMovie | Online noise removers | |
|---|---|---|---|
| One-tap audio noise reduction | Yes | "Reduce background noise" slider | Yes |
| Plain-English request | Yes | No | No |
| Video not re-encoded | Yes (audio only) | Re-renders | Varies |
| 100% offline, nothing uploaded | Yes | Yes | Uploads your clip |
| Price | Free during beta | Free | Free + upsell |
iMovie's noise slider re-renders the whole project; online tools upload your footage. Crisp cleans only the audio and keeps it local.
Why offline matters for audio cleanup
- Your footage stays yours. The "remove background noise online" tools upload your clip first. Crisp cleans it entirely on your Mac.
- Video untouched. Only the audio is processed — no quality loss on the picture, and it's fast.
- No queue, no size cap. It works on the whole file locally.
- Stack it. Denoise, then Normalize the levels — all on-device.
Clean up your audio — offline
Free to try on your Mac. One tap to knock down hiss and hum — no account, no upload, nothing leaves your device.
Download Crisp for MacApple Silicon · macOS 12+ · Notarized
FAQ
How do I remove background noise from a video on a Mac for free?
Use Crisp: drop your clip in, pick the Audio lane's Denoise mode (or type "reduce the background noise"), and press it. It cleans the audio on your Mac — no account, no upload, no watermark.
What noise does it remove?
Steady background noise — hiss, hum, AC drone, fan, low-end rumble — tuned gently so speech stays natural. It won't erase one-off sounds like a door slam.
Does it change the video?
No — only the audio is processed; the picture is stream-copied, so there's no quality loss and it's fast.
Is this the same as removing video grain?
No — that's visual noise. For grain in the picture, use Enhance or the Low-light preset instead.
Related guides
Remove wind noise · Normalize the volume · Mute / change volume · Extract the audio