PeakGlow Download

Power, glowing
around your notch.

A quiet macOS utility that turns system load into light. No Dock icon, no window. Hover the notch when you want it.

Download for macOS View on GitHub

v1.7.3 · ZIP, 2.5 MB · Notarized by Apple · Apple Silicon · macOS 27+

Mid: previews the glow at medium power.

Follows real power

Blue to cyan to green to yellow, brighter and wider as the Mac works harder.

Hover for control

An island grows out of the notch with a live reading, Glow modes, Settings and Quit.

Made for the Mac

Native SwiftUI and Metal. Respects Reduce Motion, and adapts to bright wallpapers.

Tells you when it's hot

A warm tint appears when the Mac runs hot for a sustained period.

RequiresmacOS 27 or later
HardwareApple Silicon MacBook with a notch
SignedDeveloper ID, notarized
LicenseMIT

How it works

  1. 1

    It reads system power

    PeakGlow reads the AppleSMC power sensor. A five-sample average with hysteresis decides Low, Mid or High, and the average is also mapped to a smooth position on the color ramp.

  2. 2

    Metal draws the glow

    The glow is drawn outside the notch's actual silhouette. It drops to 30 frames per second after about two seconds without a visible change, and returns to full rate the moment something changes.

  3. 3

    Hover to open the island

    Hover over the notch for about 80 ms and the controls grow out of it. Move away, click outside or press Esc and they contract back.

Five glow modes

Auto
Follows measured power from blue through cyan and green to yellow, brighter and wider as it rises.
Off
Turns the glow off.
Mid
Previews the glow at medium power (green).
High
Previews high power (yellow-green) with gentle breathing.
Hot
Previews the temperature warning, a steady orange tint.

The controls panel and menu bar offer Auto and Off. Mid, High and Hot are previews for tuning, found in Settings → Glow.

Settings, in three pages

General

Open at login, menu bar icon, hover delay and the temperature warning.

Glow

A live power meter in the glow's own colors, two power thresholds with a recommended-for-this-Mac button, and the look: idle glow, size, brightness and wallpaper. Technical sliders sit in a collapsed Fine-tuning group.

About

Details about this Mac, Copy Diagnostics, the version, credits and a link to the source.

Recommended starting points are 13 / 19 W for Air and 30 / 55 W for Pro, adjustable to your workload.

Compatibility

MacWhat happensVerified
Notched MacBook AirAir power presetsTested on MacBook Air (M2, 2022); other chips not tested
Notched MacBook ProPro power presets, extended dynamic range where the display allowsImplemented for the family; not every chip tested
External displayGlow stays on the built-in notch displayHandled in code; hardware check pending
Lid closed or no notchNo glow; open from Finder to reach SettingsSafe fallback; hardware check pending
Intel or desktop MacNot supported—

Get PeakGlow

Quit any running copy, extract the ZIP and move PeakGlow.app to Applications. Existing preferences are kept. From 1.7.1 the app is signed with Developer ID and notarized by Apple, so it opens normally.

Download v1.7.3All releases

SHA-256: 05533de1a64e8025f66b4364e9f8bbef406c55a8f3cfbb32fe520831e0895706

Recent releases

Full changelog

Questions

Why is there no window or Dock icon?

PeakGlow is built to stay quiet. Its menu bar icon shows system power and offers Auto, Off, Settings and Quit, and you can turn that icon off in Settings → General. Reopening the app from Finder opens Settings.

Does the glow show up in screenshots?

The glow and controls ask AppKit to be excluded from captures, but invisibility in every screenshot or recording tool is not guaranteed.

Is the power number a real measurement?

It comes from an AppleSMC sensor, which is not a documented public power API. It is not the same as a wall-outlet meter and can be affected by charging and hardware behavior.

Does a warm glow mean my Mac is throttling?

No. It is a temperature indicator based on a sustained high-temperature heuristic and the system's critical thermal state, not confirmation of CPU throttling or a hardware safety system.

Is it on the Mac App Store?

No. It is distributed directly. An App Store submission would need its own sandbox, signing and review work.

Something looks wrong. What do I send?

In Settings → About choose Copy Diagnostics and paste it into a bug report. It lists the Mac model, chip, macOS version, notch display, sensor status and your settings, with no serial number, user name or other personal data.

Honest limitations
  • The power reading uses AppleSMC sensors, which are not a documented public API. It may be unavailable on some models or future macOS versions, and it is not a wall-outlet meter.
  • Tested on a MacBook Air (M2, 2022). Other chips and multi-display setups are not verified on hardware.
  • A warm glow is a temperature indicator, not confirmation of CPU throttling.
  • Intel Macs and desktop Macs are not supported.

Something wrong? In Settings → About choose Copy Diagnostics and paste it into a bug report. It contains no serial number, user name or other personal data.

Credits and license

PeakGlow began as a fork of lzt66666/notchpeakglow; the original author deserves credit for the initial app and the notch power indicator idea. I maintain this version, directing the interface, refinement and releases, with AI-assisted development. It adds the interface refresh, interaction and animation work, English content, settings improvements, lifecycle fixes and the release workflow.

PeakGlow is released under the MIT License, naming the original author and me as copyright holders. The original repository's README declares MIT but has no LICENSE file, so a formal license from the original author, and confirmation of third-party obligations around the SMC reference, would still be needed before a Mac App Store submission. See the full credits.