How do I know my screen can display all of these correctly? I tried on three different screens, one of which I know is bad, and got 16, 16, 18. Is those two mistakes the error margin of the screen if my eyes are fine, or much more likely to be the error margin of my eyes?
For those reporting scores: please also report device type, like LCD/OLED, or which phone model if applicable. Tweakers.net has a large database of screen color measurements. As mentioned in e.g. https://news.ycombinator.com/item?id=43746400, it can make quite a difference
My 18 score was on an Oppo Reno8, the 16 score on the not-known-bad screen is some ~2008 display. On the former, Tweakers reports an average color error of 3.42 ΔE2000, 9.58 ΔEITP, or 2.60 ΔE2000 if white is excluded