Cap the Maximum Volume of One Loud App on Mac

macOS has no built-in way to cap the maximum volume of one app. A loud program plays at whatever your system volume is set to. Here's what macOS can do, and how to hold one app at a fixed lower level while everything else stays where it is.

Why one app can suddenly blast you on a Mac

The volume slider in the menu bar or Control Center is a single system-wide control. Every app plays at that same level.

That has a real effect on your ears. Set the system volume high to hear a quiet podcast or a soft video call, then switch to a game, a notification sound, an ad-heavy website or a video mastered much louder, and that app plays at the full system level too. The result is a sudden wall of sound at a volume you never meant for that app.

If you have tinnitus or sound sensitivity, or just care about your hearing, that's the real problem. You don't want everything quieter. You want one loud app to never go above a level you've decided is safe.

What macOS can do

Try these first:

• The app's own volume. Media players, many games and call apps have a volume slider in their settings. If the loud app has one, turn it down there. It affects only that app.
• Notification sounds. If the loud part is alerts, turn off sounds for that app in System Settings > Notifications.
• Headphone safety. If your Mac shows a Headphone Safety option with "Reduce Loud Audio" in Sound settings, it limits overall headphone loudness. It applies to everything, not one app.

The limits:

• System volume lowers everything at once. Turn it down to tame one app and your quiet apps become hard to hear.
• Many apps have no volume control at all. Plenty of native apps and web pages only follow the system level.
• Hardware sets the top end. How loud "100%" feels depends on the app's own mastering and your headphones or speakers. Software can lower one app's level reliably; it can't change your headphones.

So the practical goal is simple: hold one app at a fixed fraction of the system output so it can't surprise you.

How to cap one app with a per-app mixer

A per-app volume mixer lets you set each app's level on its own. Here's how with SoundDial, which lives in the menu bar:

1. Open the mixer. Click the SoundDial icon in the menu bar. Every running app has its own slider.
2. Find the loud app. For example a game, a browser or a call app.
3. Set its ceiling. Drag that app's slider down to your safe level, say 35 to 50%. It now plays at that fraction of the system output, and every other app stays where it was.
4. Leave the system volume where you need it. Keep it high enough for your quiet apps. The loud app stays reined in.

Because the level is per app, you're setting a maximum for that one program: even its loudest content now plays at your chosen fraction. More on this in per-app volume control on Mac.

SoundDial remembers the level you set for each app (Settings > General > Default volume for new apps: Remember last). Mute is not remembered, and an app you open later may need a touch of its slider before the saved level applies, so check the loud app's slider after relaunching it.

If one app keeps firing loud alerts, per-app mute silences it without touching anything else.

Lowering an app's level works well for capping it, but it's one layer of protection, not a medical safeguard. If you have tinnitus or sound sensitivity, pair it with sensible overall listening levels and breaks.

The other direction: boost

The same slider goes the other way too. A too-quiet app can go above 100%, up to 200%, without making the rest louder. For hearing protection you just choose the "down" direction and leave it there.

The short version

macOS can't cap a single app's volume on its own. Use the app's own volume control if it has one. If it doesn't, SoundDial, a per-app volume mixer for Mac, holds that app at a fixed lower level while your other apps stay audible. It needs macOS 14.2 or later and costs €14.99 one-time purchase on the Mac App Store, no subscription.

Get SoundDial on the Mac App Store.