Paint Color Mixer Calculator
Scale a paint mixing recipe to any batch size, keeping the proportions exact.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Mixing paint is a ratio problem, so scaling a recipe means multiplying every part by the same factor rather than adjusting one colour. Working in parts also makes it easy to mix a small test batch first and scale it up once the colour is right.
Worked example
calculated with the default values below
First colour name Titanium White · Parts of the first colour 6 · Second colour name Ultramarine Blue · Parts of the second colour 2 · Third colour name (optional) Burnt Sienna · Parts of the third colour 1 · Batch size you want 500 ml Total parts 9.0 · Amount of first colour 333.3 ml · Amount of second colour 111.1 ml · Amount of third colour 55.6 ml · First colour share 66.67 % · Second colour share 22.22 % · Third colour share 11.11 % · Scaled recipe Titanium White: 333.3 ml | Ultramarine Blue: 111.1 ml | Burnt Sienna: 55.6 ml
General background references
Disclaimer
These calculators provide planning estimates only. Building codes, wiring regulations and safety requirements differ by country and change over time, and nothing here replaces a licensed professional or a permit. For structural, electrical or gas work, follow local code and have the installation inspected.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
a_i = p_i × B ÷ (p1 + p2 + p3); q_i = p_i ÷ (p1 + p2 + p3) × 100
- p_i
- Parts of colour i (i = 1, 2, 3)
- B
- Total batch size (ml)
- a_i
- Amount of colour i (ml)
- q_i
- Share of colour i (%)
Negative parts are clamped to 0; recipe amounts are rounded to 0.1 ml, percentages keep full precision.
Frequently asked questions
Why does the mixer scale every colour by the same factor as the batch?
It treats your recipe as parts, not fixed volumes, so 6:2:1 totals 9 parts and a 500 ml batch gives 55.6 ml per part. The first colour is then 333 ml (66.7%), the second 111 ml (22.2%) and the third 56 ml (11.1%). Because every part scales together, a test batch of 50 ml keeps the exact same ratios, so you can mix small and scale up without reworking the numbers.