Paint Color Mixing Calculator

What Is a Paint Color Mixing Calculator?

It estimates the color you get when you combine paints in given proportions, and how much of each paint a batch needs. Enter each color as a hex code (from a paint maker's color page, a photo, or our Hex to RGB Converter) and the number of parts. The estimate uses the Kubelka-Munk model, the standard way to describe how pigment layers absorb and scatter light, applied to the red, green and blue channels. It captures why blue and yellow make green rather than gray, and why a little black darkens a lot of white, but real pigments have spectral curves that three channels cannot describe, so two paints with the same hex code can mix differently. To work out how many gallons a room needs, use the Paint Calculator.

Swatch: the latest predicted mix.

Primary Color Mixing Results

Understanding Color Theory for Paint Mixing

Paint mixing follows subtractive color theory, where combining pigments absorbs more light and produces darker results. This is the opposite of additive color mixing used in screens, where combining light produces brighter results. The subtractive primary colors are red, yellow, and blue (or more precisely, magenta, yellow, and cyan in printing). Mixing any two primaries produces a secondary color: red and yellow make orange, blue and yellow make green, and red and blue make purple. Tertiary colors result from mixing a primary with an adjacent secondary, creating shades like red-orange, yellow-green, and blue-violet.

Complementary colors sit opposite each other on the color wheel. Mixing complementary colors in paint creates muted, brownish tones because the combination absorbs most of the visible spectrum. This property is useful for toning down overly bright colors without adding black, which can make colors look muddy. Adding a touch of green to an overly vivid red, for example, produces a richer, more natural red. Understanding these relationships helps you predict mixing results and correct off-target colors.

Choosing the Right Paint Finish

Paint finish (sheen level) affects both appearance and durability. Flat or matte finishes hide wall imperfections but stain easily and are difficult to clean, making them best for ceilings and low-traffic rooms. Eggshell offers a slight sheen with better washability, suitable for living rooms and bedrooms. Satin provides a soft luster and cleans well, making it the most popular choice for kitchens, bathrooms, and hallways. Semi-gloss resists moisture and scrubs clean easily, ideal for trim, cabinets, and doors. High-gloss creates a mirror-like finish that highlights imperfections but is extremely durable, typically reserved for accent pieces, furniture, and front doors.

Higher-sheen paints reflect more light, making colors appear slightly lighter and more saturated compared to flat paint of the same color. This means a color chip viewed on a flat card may look different when applied in semi-gloss. Paint stores can adjust formulations to compensate, but testing a sample on the actual surface under your room's lighting conditions is always the most reliable approach. Calculate project costs for larger renovations with our Fence Calculator and Deck Calculator.

Color Matching and Custom Mixing Tips

When mixing custom colors, always mix more than you think you need. Recreating an exact custom shade is extremely difficult because even small measurement variations change the result. If you need two gallons, mix three to ensure consistency across all walls. Start with the lighter base color and gradually add the darker color, mixing thoroughly after each addition. Record exact quantities so you can replicate the formula if needed. Use a paint mixing drill attachment for large volumes because hand stirring rarely achieves complete uniformity. Test the mixed color on a white surface and let it dry completely before judging, as wet paint typically dries one to two shades darker. For color code conversions between hex, RGB, and other formats, use our Hex to RGB Converter.