Color Mixing Calculator

This calculator tracks the volume and cost math behind custom paint tinting, where a base paint (converted here from gallons to fluid ounces at 128 oz/gallon) is combined with up to four separate colorant tints, each entered in fluid ounces. Total tint volume is simply the sum of all four tint amounts, and total mixed volume is base volume plus total tint volume, converted back to gallons for the headline output. Tint percentage — a useful number for matching a formula later or scaling it up or down — is total tint volume divided by total mixed volume, expressed as a percentage; note that because tint volume is added on top of the base rather than measured out of it, a can that starts as exactly 1 gallon of base paint will end up slightly over a gallon once tint is stirred in, which is accounted for correctly here but is a common point of confusion when comparing to a paint store's premixed gallon cans.

Cost is calculated straightforwardly: base cost per gallon times gallons of base, plus each tint ounce times a single flat cost-per-ounce rate, added together for total cost. A key simplification is that this calculator applies one uniform tint cost per ounce across all four colorants, when in reality different pigment concentrates (especially deep-base or high-chroma tints) often cost more per ounce than standard universal colorants — if your tints vary significantly in price, you'll need to price them separately and adjust the total cost by hand. Always record your exact tint amounts on the can label immediately, since even small ounce-level differences compound into visible color mismatches on refill batches.