Apps similar to Brightintosh include Twinkle Tray, which is free and open source. Other options are Solace, Dimly, MonitorControl and Monitorian. There's no shortage of Screen Dimmers like Brightintosh, with more than 25 alternatives for Mac, Windows, Linux and Android.
LiteBright is a lightweight native brightness controller for Windows 10 and 11. It lets you control brightness across multiple monitors from the system tray, adjust displays independently or together, and use global keyboard shortcuts for quick changes.
LUMEL is a two-way Mac brightness app: boost a supported XDR display past the macOS cap toward ~1600 nits for sunlight, or dim below the system minimum for dark rooms — all from the menu bar. Public EDR rendering, sandboxed, no data collected. Free tier never expires; $2.99 one-time Pro.
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