Monitor Switch

Overview

Monitor Switch is a free, open-source service for changing a monitor’s input and DDC/CI settings from a browser, API, scripts, or Home Assistant. It suits people sharing a monitor between computers who are willing to set up a Raspberry Pi. Its range of controls and automation hooks is useful, but setup demands and limited hardware verification make compatibility worth weighing carefully.

Key features

Input switching is the main reason to choose Monitor Switch: a Raspberry Pi attached to the monitor can handle source changes without requiring software on each computer. When the monitor exposes them, the service also controls brightness, contrast, volume, mute, picture mode, colour temperature, RGB gain, and black level. It can read usage hours, firmware level, refresh rates, and power state, giving users more than a simple input toggle.

Editable profiles define monitor values and can override capability detection when a monitor reports its controls incorrectly. Home Assistant discovers profile features through MQTT and exposes them as entities such as selectors, sliders, and sensors. That makes the service a stronger fit for users who want monitor controls in home-automation routines than for someone seeking a conventional desktop utility.

There are meaningful operational limits. Switching to a computer that is off can leave the display black, and the service cannot identify that situation in advance. After an input change, a full reread of monitor values takes around 20 seconds on a Pi Zero, so other readings may briefly lag. Home Assistant state is polled from the monitor, with input-source polling set to 15 seconds by default.

Pricing

Monitor Switch is free and open source under the MIT license. The MIT-licensed open-source software plan costs nothing; it is described as usable but not yet released and requires a Raspberry Pi. There are no paid tiers to compare, but the zero-price entry does not remove the hardware and setup costs: installation requires Raspberry Pi OS, an HDMI connection to the monitor, and SSH access to the Pi.

Platforms

Monitor Switch supports web access, Linux, an HTTP API, and self-hosted Raspberry Pi deployment. The Pi runs the service and connects to the monitor over HDMI; installation uses an Ansible playbook. The service has no authentication and is intended for a trusted LAN. It binds to a configurable address rather than 0.0.0.0 by default, but that should not be mistaken for account-level access control.

The project reports real-hardware checks with a Samsung Odyssey G9 and Raspberry Pi Zero 2 W; other monitors have not been verified. Since its controls depend on what a monitor exposes through DDC/CI, users with other hardware should treat compatibility as uncertain rather than assume every listed control will work.

Who it's for

Monitor Switch is best for technically comfortable users who regularly switch a monitor among computers and want centralized controls or Home Assistant integration. It is less suitable for anyone who needs a polished, released product, broad confirmed monitor compatibility, or protection beyond a trusted-LAN deployment. It also cannot prevent a black screen if the selected computer is powered off.

Pros and cons

• Pro: Input changes and a broad set of monitor controls are available through one service, avoiding separate control paths for each computer.
• Pro: Editable profiles and MQTT-based Home Assistant entities support customized monitor settings and automation.
• Pro: The MIT license and free plan make the software itself available at no charge.
• Con: A Raspberry Pi, Raspberry Pi OS, SSH access, and Ansible-based installation raise the setup burden compared with a desktop-only tool.
• Con: The service has no authentication, so its trusted-LAN design rules it out for users who require authenticated access.
• Con: Hardware verification is limited to one reported monitor model, and an off computer can produce an undetectable black-screen outcome.
• Con: Monitor values can lag after input changes, with a full reread taking around 20 seconds on a Pi Zero.

Alternatives

For a Linux-based DDC/CI approach without the Raspberry Pi service model, consider ddcutil, a free, self-hosted API tool maintained by Sanford Rockowitz. ASUS monitor owners who want a free download for Windows or macOS should consider ASUS DisplayWidget Center, which is limited to compatible ASUS monitors. For supported AOC devices on Windows, AOC G-Menu is another free option.

Users with supported LG monitors who prefer Windows or macOS can choose free LG OnScreen Control. Mac users looking for a brightness-focused freemium app can consider Lunar. For Linux users who need brightness control rather than input switching, Monitor Brightness Control is a free MIT-licensed tool requiring a DDC/CI-compatible monitor and I2C access.

Windows users can also compare Twinkle Tray, which is free for Windows 10 and 11 and supports most laptops and DDC/CI-enabled monitors, or ClickMonitorDDC, free for personal use.

Browse the Monitor Control Software category for more options.

Verdict

Choose Monitor Switch if you share a monitor among computers, want input and DDC/CI controls in one place, and are comfortable running a Raspberry Pi on a trusted LAN. Its profiles and Home Assistant discovery are the strongest reasons to pick it. Look elsewhere if you need authenticated access, confirmed support for your monitor, or a released tool that can warn before switching to a powered-off computer.