The best paint conversion charts I have found are located here: https://redgrimm.github.io/paint-conversion/index.html

Example showing in the screen shot below using the example Yriel Yellow by Citidel:

  1. An equivalent or similar paint in another brand (in this case Vallejo)
  2. The original colour
  3. The mathematical difference between these 2 colours

Thanks to whoever put them up there they are great!, i hope they never disappear!‚Äč