About

Wire My Thermostat is a free tool that translates the terminal letters on your old thermostat into exact wiring for today’s popular smart thermostats. We built it because manufacturer checkers only cover their own brand, and forum answers rarely match your specific wires.

Wiring rules come from the manufacturers’ published installation and wire-label guides, and ambiguous cases (like B and X wires) are flagged instead of guessed. We are not affiliated with Google, ecobee, Resideo/Honeywell Home or Amazon.

Found an error? Please tell us. Corrections are our top priority.