Color Contrast Analyzer is called CCA for short which is an Open Source software that helps you determine the legibility of text and the contrast of visual elements, such as graphical controls and visual indicators.

This repository contains the source code for the new Colour Contrast Analyser (CCA) builds for Windows and macOS based on Electron. For the previous, non-Electron versions (“CCA Classic”), see the CCA-Win and CCA-OSX repositories.
Color Contrast Analyser v3.2.0 features：

• WCAG 2.1 compliance indicators
• Several ways to set colours: raw text entry (accepts any valid CSS colour format), RGB sliders, colour picker (Windows and macOS only)
• Support for alpha transparency on foreground colours
• Colour blindness simulator

Size: 57-79 MB
License: Open Source
Requirements: Windows 11|10|8|7|macOS
The author’s web link:https://github.com/ThePacielloGroup/CCAe