Why not just buy pre-mixed colours?

Mixing your own colours gives you far more control over hue, saturation and value. You can match any colour exactly and develop a deeper understanding of colour relationships. It also reduces the number of tubes you need to carry.

Do oils and acrylics mix differently?

Yes. Acrylics dry slightly darker and shift in hue. Oils stay true to the wet mix. Watercolours dry lighter. Always test your mix on a scrap piece and let it dry before applying to your painting.

What does "parts" mean in a mixing ratio?

Parts are relative proportions, not absolute amounts. If a mix calls for 3 parts red and 2 parts yellow, you could use 3 ml red and 2 ml yellow, or 3 knife-loads of red and 2 of yellow. The ratio stays the same.

How do I make colours less intense?

Add the complementary colour in small amounts to reduce saturation without changing value. For example, add a touch of green to dull a red. Alternatively, add grey or a mix of all three primaries. Avoid adding black, which can create muddy results.

Colour Mixing Ratio Calculator — Paint Mixing Guide

Work out primary colour ratios to mix a target colour family for any paint medium.

Paint MediumChoose the paint you are mixing — adjusts white to offset the drying shift (acrylic darker, watercolour lighter)

Target Colour FamilyPick the colour family you want to mix — e.g. greens, skin tones, chromatic greys

Lightness

1 = very dark, 10 = very light

Warmth

1 = cool, 10 = warm

How We Calculate This

How Colour Mixing Ratios Work

Pigment parts = colour family recipe × warmth × opacity

Each colour family starts from a base ratio of the RYB artist primaries — green is yellow + blue, purple is red + blue, earth tones lean on red + yellow. The warmth slider shifts the balance towards warm (more red/yellow) or cool (more blue). Lightness sets how much white and black to add. The opacity factor thins the whole pigment load uniformly for glazing, so the recipe ratio holds while the charge drops. The paint medium nudges the white amount to offset the drying shift — acrylic dries darker so it adds a little more white, watercolour dries lighter so it holds white back.

Frequently Asked Questions

Last updated: March 2026

All calculations are estimates. Always verify quantities before purchasing materials.