If you’re a decaffeinated coffee drinker don’t you hate having to trust the person behind the counter to give you the right cup of coffee? Or how about when you get a cup of coffee in a conference room and your only clue about whether the pot contains regular or decaf is a chintzy table sign? Here is the definitive answer to “is that decaf”. Use these 20 test strips on a sample of coffee. Insert a strip into a sample of coffee and if it turns brown you’ll know you have regular coffee. These strips detect caffeine above a 20mg to 6 oz ratio. Works with hot or cold beverages (but not latte).