go-sct GoDoc

A color temperature setting library and CLI that operates in a similar way to f.lux and Redshift.

The command line app automatically determines your location using GeoIP and adjusts the color temperature depending on time.

$ go get -u github.com/d4l3k/go-sct/sct

$ sct # Launch in background
$ sct 3000 # One time temperature change. Temperature must be 1000-10000.

This requires Go and (the Xrandr library or Windows).


By default, the lowest color temperature allowed is around 4500K. More
information is available here

There is a workaround to allow all possible adjustments by alterting the registry.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ICM]

Save the above as a file with a “.reg” extension and double click to apply.


Setting the color temperature uses a port of sct in Go. Credit goes to him for figuring out how to do this.

go-sct also provides the geoip package which is a packaged version of


go-sct is licensed under the MIT license. geoip and sct are copyrighted by their respective owners.

Made by Tristan Rice.


View Github