/threads/match
Match a colour to a thread
Pick the colour you have in mind and read off the nearest real thread in each of the four ranges. There is no code to know first.
Or start from a colour family
The nearest thread in each range
Three for each range, closest first, measured the way the editor measures a colour match. Every code opens that thread's own page.
DMC
Anchor
Madeira
Cosmo
The measure is CIEDE2000, the same one the editor uses to match a thread to a picture, and the number is how far apart the two colours are on it; under 1 and nobody could tell them apart.
The colours on this page are our screen values for the threads, not the makers'. No thread maker publishes one, so every chart on the web is somebody's estimate, this one included. Use it to compare shades against each other, and buy from a real shade card.