The best open source alternative to Sip is gpick, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to Sip and 14 is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Sip are Instant Eyedropper (Free, Open Source), gcolor2 (Free, Open Source), Colora (Free, Open Source) and Colorpicker (Free, Open Source).
Instant Eyedropper is a free color detection tool for webmasters that will identify and automatically paste to the clipboard the HTML color code of any pixel on the screen with just a single mouse click.
gcolor2 is a basic colourpicker utility that allows you to select any colour on your screen, and, well, grab it's colour. It also allows you to save the colour you create to a file, which shows up as a list in the application.
Colorpicker is efficient through its interface. Every features are accessible from the toolbar and shortcuts. You have the possibility to choose any color thanks to the three RGB sliders (soon HSL, CMYK, ...)!
Chroma is a browser-based color picker that focuses on color selection. It was built using React Color. FEATURES - Focuses on color selection while active, but gives a full view when not - Keyboard commands - Simple, easy to use design - Provides HEX, RGB and HSL codes
Pika (pronounced pi·kuh, like picker) is an easy to use, open-source, native colour picker for macOS. Pika makes it simple to quickly find colours on screen, in the format you need, so you can get on with being a speedy, successful designer.