I think this is my new favorite online contrast checker tool. It's called "Contrast Report", and includes a lot of features I need (or didn't know I needed but like).
The tool (by Adam Chaboryk) https://contrast.report/
List of nice features:
- check for AA and AA
- option to check for normal, large text and graphics and UI elements (the 3:1 rule)
- option to "fix", that will automatically recommend a color combination that is as close as possible to the original.