What two colors make cerulean blue?

Chromilla's watercolor recipe uses 3 tubes rather than two: 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue. Viridian Green leads the mix. Chromilla's model predicts a 90% dry match against the target, scored against its own color model, not a measured paint-out.

What is the hex code for cerulean blue?

Chromilla uses #3A78A5 as the target for cerulean blue. The watercolor recipe is predicted to dry to about #2B6E9D.

Can I mix cerulean blue without black?

Yes. Chromilla's watercolor recipe uses no black: 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue.

How to Mix Cerulean Blue in Watercolor

Quick answer

To mix cerulean blue (#3A78A5) in watercolor, use 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue. Chromilla's model predicts a 90% dry match against the target, scored against its own color model, not a measured paint-out. Chromilla is a web-based paint color mixer that turns any color, from a photo, the camera or a hex code, into exact paint-tube ratios for acrylic, oil and watercolor, using Kubelka-Munk pigment mixing and aiming at the color after it dries.

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Target

Cerulean Blue

#3A78A5

Predicted dry result

90% match when dry

Mix to #3078A8 while wet. It dries to about #2B6E9D.

Cerulean Blue in watercolor: tube ratios, and ml for a 100 ml batch
Paint	Pigment	Parts	Share	100 ml batch
Viridian Green	PG18	2	51%	51 ml
Titanium White	PW6	1	25%	25 ml
Phthalo Blue	PB15	1	24%	24 ml

How we calculated this: Kubelka-Munk pigment mixing, then a per-medium dry shift, scored with CIEDE2000. Method and accuracy benchmark. Last checked August 2026.

Terms used here: Tinting strength, Dry shift, Kubelka-Munk, Delta E (dE2000), Pigment code, Gamut.

A soft, opaque sky blue. Slightly green-leaning and calm. This guide gives you the pigment ratios that land on #3A78A5 in watercolor, using the same solver that powers the Chromilla mixer.

Pigment recipe

Checked August 2026

Ratios calibrated for watercolor. Start with the dominant pigment, add the modifiers in the order below, and adjust in 5% steps to your target swatch.

1. Viridian Green
PG18
51%
2. Titanium White
PW6
25%
3. Phthalo Blue
PB15
24%

What colors make Cerulean Blue?

Viridian Green, Titanium White, and Phthalo Blue, in roughly a 51:25:24 ratio.

How to make Cerulean Blue in watercolor

Start with Viridian Green at about 51% as your watercolor base, then work in Titanium White and Phthalo Blue in the order above. Adjust in 5% steps until the swatch reads #3A78A5.

Why mix Cerulean Blue instead of buying it

Mixing Cerulean Blue yourself lets you approximate an expensive or hard to find tube from pigments you already own, match Cerulean Blue across paint brands whose factory tubes differ, and rebuild the exact color when you run out mid painting. The recipe above is the working starting point.

Common mistakes

That pigment is a very strong tinter, add it a touch at a time or it will swallow the mix. White cools and chalks a mix as you add it, so tint in small steps and stop before it goes pastel.

Variations on Cerulean Blue

Each variation is its own target (lighter and darker move OKLCH lightness by 0.08; warmer and cooler turn the hue 12 degrees toward red or blue), solved fresh.

Lighter Cerulean Blue

#5290BF

76% Titanium White, 19% Phthalo Blue and 5% Alizarin Crimson. Chromilla's model predicts an 89% dry match against the target, scored against its own color model, not a measured paint-out.

Darker Cerulean Blue

#20608C

12 parts Phthalo Blue, 7 parts Titanium White and 1 part Burnt Umber. Chromilla's model predicts a 93% dry match against the target, scored against its own color model, not a measured paint-out.

Warmer Cerulean Blue

#4A74A9

9 parts Titanium White, 3 parts Phthalo Blue and 2 parts Alizarin Crimson. Chromilla's model predicts a 90% dry match against the target, scored against its own color model, not a measured paint-out.

Cooler Cerulean Blue

#4A74A9

9 parts Titanium White, 3 parts Phthalo Blue and 2 parts Alizarin Crimson. Chromilla's model predicts a 90% dry match against the target, scored against its own color model, not a measured paint-out.

Cerulean Blue questions

What two colors make cerulean blue?: Chromilla's watercolor recipe uses 3 tubes rather than two: 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue. Viridian Green leads the mix. Chromilla's model predicts a 90% dry match against the target, scored against its own color model, not a measured paint-out.
How do you make cerulean blue paint lighter without losing the hue?: Re-balance the mix instead of only adding white. For a lighter cerulean blue (#5290BF) in watercolor, Chromilla mixes 76% Titanium White, 19% Phthalo Blue and 5% Alizarin Crimson. Chromilla's model predicts an 89% dry match against the target, scored against its own color model, not a measured paint-out.
What is the hex code for cerulean blue?: Chromilla uses #3A78A5 as the target for cerulean blue. The watercolor recipe is predicted to dry to about #2B6E9D.
Can I mix cerulean blue without black?: Yes. Chromilla's watercolor recipe uses no black: 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue.

Cerulean Blue in other mediums

Cerulean Blue in Acrylic: 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue, predicted 88% dry match by Chromilla's color model.
Cerulean Blue in Oil: 2 parts Viridian Green, 1 part Titanium White and 1 part Phthalo Blue, predicted 97% dry match by Chromilla's color model.

Get this recipe for your paint brand

Open the live mixer with Cerulean Blue + watercolor pre-loaded and calibrate to your tubes.

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Technique guides for this color

Related mixing guides

Pigment mixing is subtractive, so small ratio changes matter. The mixer refines this recipe to your brand and updates on the fly.