A pinch is a small, indefinite amount of a substance, typically a powder like salt, sugar, spice, or snuff.[1] It is the "amount that can be taken between the thumb and forefinger".[2]
Some manufacturers of measuring spoons and some U.S. cookbooks give more precise equivalents, typically 1⁄8, 1⁄16,[3] or even 1⁄24 teaspoon,[4] but there is no generally accepted standard.
recently kitchen supply stores... have begun selling sets of "minispoons" in which the spoon labeled "pinch" is designed to hold exactly 1/2 dash or 1/16 teaspoon, which is roughly 0.01 fluid ounce or 0.3 milliliter.