How to Remove Coffee Stains From Carpet

No matter what color carpet you have, first try to blot up as much of the coffee as you can, then sponge the area with cool water and blot. Then, mix 1/4 teaspoon of liquid dish soap, one tablespoon of white vinegar, and one cup of warm water. Using a clean, white cloth, sponge the stain with the mixture, applying a little bit at a time and blotting frequently with a dry cloth until the stain disappears. Add one or two more drops of dish liquid to the vinegar/water mix, if needed. Sponge with cold water to rinse and blot dry.

Credit: https://www.goodhousekeeping.com/home/cleaning/a47654/how-to-clean-carpet/