Extra Dim

A tiny screen dimmer and eye-care tool for Windows.

Source on GitHub · MIT

Dimmer than Windows allows. Dim up to 90% with smooth fades, per display if you like.
Easy on the eyes. Warms the screen by color temperature while keeping blacks black.
Practically weightless. About 50 KB, a few MB of memory and zero CPU when idle.
Out of the way. Click-through, never steals focus, and screenshots still show the normal screen.

No install needed.

Features

Dim: Up to 90% darker, never fully black, with smooth fades.
Eye care: Warms the screen from 6500K to 3400K (4800K by default). Colors are scaled directly, like Night Light, so blacks stay black, and they are restored on exit or crash.
Multiple displays: Adjust displays together or separately; adapts when displays change.
Out of the way: Click-through, never steals focus, hidden from Alt+Tab, and screenshots and screen sharing show the normal screen.
Controls: Tray icon: left-click for the panel, middle-click to pause. Ctrl+Alt+PgUp / PgDn for brighter or darker, Ctrl+Alt+End to pause.
Lightweight: About 3 MB of memory when idle, no polling timers, and efficiency mode on Windows 11.

Windows: Put ExtraDim.exe somewhere like %LOCALAPPDATA%\Programs\ExtraDim and run it, then turn on Start with Windows in the panel. No admin rights needed.