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A faint tint over your live screen. Video keeps playing and the clock keeps ticking. Set it anywhere from 2% to 50%.
Menu bar app for macOS 26
Lock your Mac.Keep the screen on.
Step away and Dimma Screen covers every display with a tint you can barely see. Your desktop stays lit and keeps moving, so it looks like you’ll be right back. Touch a key or the mouse, and it asks for your PIN.
Back in 5
Back around 15:02
Enter PIN
Demo PIN 2580
Stepping away shouldn’t look like leaving
The macOS lock screen goes dark and puts up the login window. Anyone walking by can tell you’ve gone. Dimma Screen leaves your desk the way it was and keeps your work out of reach.
| Aspect | macOS lock screen | Dimma Screen |
|---|---|---|
| The display | Goes dark soon after you lock | Stays on for 30 minutes to 4 hours |
| What people see | The login window | Your desktop under a faint tint, or a color, a snapshot, or a picture |
| To get back in | Login password or Touch ID | PIN, login password, or Touch ID |
| Built for | Security | Privacy from people nearby |
Menu bar › Lock and Keep Awake
The screen stays on as long as you need
Choose 30 minutes, 1 hour, 2 hours, or 4 hours. The display stays lit and your Mac stays awake, so downloads and builds keep running.
When the time is up, your Mac follows its usual energy settings again. The cover stays, and it still takes your PIN to get back in.
Leaving for longer? Choose Lock, Then Lock Screen. When the time runs out, Dimma Screen hands over to the macOS lock screen.
Lock and Keep Awake › 1 hour
Screen on
Energy settings apply
Lock, Then Lock Screen › 1 hour
Screen on
macOS lock screen
Dimma Screen cover, PIN to unlockDisplay on, Mac awake
Settings › Display › Show
Choose what the screen shows
Solid Color
One color on every display. Nothing on screen shows through.
Snapshot at Lock
Your screen exactly as it looked when you locked. It stays in memory and is cleared when you unlock. Needs Screen Recording access.
Custom Image
A picture of your choice, scaled to fill each display.
A little motion against burn-in. Pixel Shift, Breathing Brightness, and Gradient Drift keep the picture from sitting still. At Subtle, the default, Pixel Shift moves a snapshot or image 2 points every 45 seconds. Pick a stronger setting if you don’t mind people noticing. With Reduce Motion on, nothing moves.
| Strength | Pixel Shift |
|---|---|
| Subtle | 2 pt every 45 s |
| Medium | 6 pt every 20 s |
| Noticeable | 16 pt every 10 s |
Menu bar › Away Note
Leave a note on the screen
Write one line, like “Back in 5” or “This room is taken.” It shows on every display with the time you’ll be back. One click locks your Mac, keeps the screen on, and puts up the note.
Back in 5
Back around 14:35
This room is taken.
Back in 10.
Back in 10.
Back around 14:40
Any key, any click
Your PIN, right where you’re looking
Touch the keyboard or mouse and a small glass panel fades in on the display under the pointer. Type your 4- to 8-digit PIN. It unlocks the moment the last digit is right. There are no buttons to find.
- Your first keystroke counts. Start typing the PIN right away.
- Forgot your PIN? Type your login password and press Return. Touch ID works too.
- Leave it alone for 5 seconds and the panel fades away. Your typing is cleared.
Small things that matter when you’re away
Every display
Covers every display, every Space, and full-screen apps. A display you plug in while locked is covered too.
Locks on its own
Lock after 5, 10, 20, or 30 minutes or an hour without input. Or set your own keyboard shortcut.
A low profile
The app, its process, and its windows are named just Dimma. Until someone touches the Mac, the menu bar keeps showing the app you were using.
Your PIN stays private
Only a salted hash of your PIN is kept, in your login keychain. Snapshots stay in memory and are cleared when you unlock.
One lock at a time
If macOS locks the screen while the cover is up, Dimma Screen steps aside. You only unlock once.
Seven languages
English, 简体中文, 繁體中文, 日本語, 한국어, Deutsch, and Français. It follows your Mac, or you can pick one in Settings.
Questions
Is Dimma Screen a mouse jiggler?
No. It doesn’t move the pointer or type for you. It keeps the display on and covers it. Your Mac keeps counting keyboard and mouse idle time as usual.
Can it replace the macOS lock screen?
No. Dimma Screen is a privacy overlay. It keeps coworkers walking past and the person in the next seat off your screen. When you need real security, press ⌃⌘Q, or use Lock, Then Lock Screen.
What if I forget my PIN?
Type your login password on the panel and press Return. On a Mac with Touch ID, your fingerprint works too.
Does it put my Mac to sleep or start the screen saver?
No. While the screen is on, Dimma Screen holds off display sleep, idle sleep, and the screen saver. Closing the lid or choosing Sleep still puts your Mac to sleep.
What permissions does it need?
Accessibility, so keystrokes go to the PIN panel and not to the app underneath. Screen Recording only if you choose Snapshot at Lock.
Which Macs does it run on?
Macs with Apple silicon running macOS 26 Tahoe or later.
Dimma Screen for Mac
Version 1.0 is in final testing. The first signed and notarized build will be posted on this page.
- macOS 26 Tahoe or later
- Apple silicon
- Accessibility access