Whenever one creates a web application, one probably needs some shades of gray: for the text, for the background, for shadows, and much more. In my experience, I usually pick rather light colors for dark gray and rather dark colors for a light background gray/white which—if not corrected—won’t make the app look cool. For people who have the same issues, I’ve created a survey of grays that are around the web. The selection of websites is very subjective. As it turns out, there is a lot of nuance to the last few least significant bits of the color code.
Light gray
#ffffff Indico, Gitlab
#f8f9fa Boostrap
#f7f7f7 Jupyter cell
#f6f6f6 Service now
#f1f3f4 Google
#f1f1f1 Youtube dark background
#eeeeee Jupyter
#ececec Indico file
#e8e8e8 Gitlab dark sidebar
#e6e6e6 Service now, button over from white
#e0e0e0 Indico file over with gradient
Medium gray
#777777 Indico
#6c757d Bootstrap gray
Dark gray
#424242 Indico
#343a40 Bootstrap
Text
#707070 Gitlab grayed user input
#6c757d Bootstrap text muted, secondary
#2e2e2e Gitlab
#212529 Bootstrap
Shadows
rgba(0, 0, 0, 0.1) Indico
rgba(0,0,0,.12) Google menu bar
rgba(87, 87, 87, 0.2) Jupyter
rgba(0,0,0,.14) Google menu bar
rgba(0,0,0,.2) Google menu bar
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