See the pairings section below for calculated harmony options.
Common uses
See uses & contexts below for interiors, fashion and practical guidance.
Accessibility snapshot
Pairs better with white text (13.4:1) than black (1.6:1).
See this colour in the real world
Colours in photographs vary with lighting, material, camera processing and screen calibration — the named colours below are visual approximations, not exact measurements.
Pigment
Prussian blue, first produced in Berlin around 1706, is widely credited as the first modern synthetic pigment.
The glass dish and pale backdrop occupy more of the frame than the pigment itself, so an automated whole-frame scan would be dominated by grey and white rather than the blue pigment — the palette above was hand-picked from the pigment mound.
Before Prussian blue's accidental discovery around 1706, a strong, stable blue meant paying for natural ultramarine's enormous cost — Prussian blue was significantly cheaper to produce and is widely credited as the first modern synthetic pigment, genuinely changing what a working painter (not just a wealthy patron) could afford to use.
In practice: Prussian blue's affordability is a real, documented milestone in the much longer story of colour becoming cheaper and more widely available — a trend that continued through the 19th-century synthetic-dye boom.
These HEX values are a modern digital approximation for comparison — they cannot exactly reproduce a historical physical pigment, dye or dyed cloth, whose appearance also varied by batch, ageing and the light it was viewed in.
Pairings
Calculated from Prussian Blue’s position on the HSL wheel (hue 205°, saturation 100%, lightness 16%). Colour-wheel pairings are a design convention, not a guarantee: check any pairing in the light and material you will use it in.
International Klein Blue is the closest, at ΔE00 11.8 from prussian blue: 7 points lighter, 52 points more saturated and 30° round towards blue. That is clearly different, though many people would use one name for both.
Charcoal is next, at ΔE00 11.9 from prussian blue: 9 points lighter, 16 points less saturated and 21° round towards green. That is clearly different, though many people would use one name for both.
Midnight Blue is next, at ΔE00 12.2 from prussian blue: 3 points darker, 34 points more saturated and 34° round towards blue. That is a different colour at a glance.
Cobalt Blue is next, at ΔE00 12.2 from prussian blue: 13 points lighter, 38 points more saturated and 22° round towards blue. That is a different colour at a glance.
Worked out from this colour’s own measurements — its lightness, saturation and undertone — rather than written for it. That is why the guidance differs from one colour to the next even when the two look similar.
What role it can play
This works across a range of sizes. At chroma 25 it is assertive enough to register on a small object and restrained enough not to dominate a wall.
Walls and large surfaces
strong
Chroma 25 sits inside the range walls and large surfaces carry without taking over the room. At L*19 it also absorbs a good deal of the light in the room, so plan the lighting alongside it rather than afterwards.
Secondary surfaces
strong
Chroma 25 sits inside the range secondary surfaces carry without taking over the room.
Furniture
strong
Chroma 25 sits inside the range furniture carry without taking over the room.
Rugs, curtains and bedding
strong
Chroma 25 sits inside the range rugs, curtains and bedding carry without taking over the room.
Trim and joinery
strong
Chroma 25 sits inside the range trim and joinery carry without taking over the room.
Accents and small objects
strong
Chroma 25 is exactly what an accent is for. The saturation that makes this difficult across a wall is the reason it works on a cushion, a door or a single chair.
As an accent: tonal anchor
Too quiet to be an accent but definite enough to build a tonal scheme around — several depths of this hue will read as considered rather than as timid.
Warm bulbs emit little short-wavelength energy, so there is less for a blue to reflect. There is enough chroma here to survive it, though it will read warmer and slightly duller.
Under cool bulbs
Cool light flatters this — it will hold its identity and may read slightly more saturated than in warm light.
In daylight
Deep colours hold their identity in daylight better than pale ones, because there is more of the range left to work in. This will look most like itself in good indirect light.
In a dim room
At low light levels the eye's colour discrimination genuinely falls and deep colours converge toward each other. This will read as "dark" rather than as its own colour in a dim room unless it is lit.
Compared with the sample card
Already deep, so there is little further to fall — but on a large matte surface it will absorb enough light to look flatter than the sample.
Oak · Walnut · Pine · Plywood · Light wood (ash, birch, beech) · Dark wood · Reddish wood (mahogany, cherry, teak)
works well
Opposite in undertone to Oak, Walnut, Pine, Plywood, Light wood (ash, birch, beech), Dark wood and Reddish wood (mahogany, cherry, teak), but 3–66 points apart in lightness or far enough round the hue circle that the difference reads as deliberate contrast rather than as a clash.
The amount of timber matters as much as the tone: one piece is an accent, a floor plus joinery is the room’s dominant colour. More on working with wood tones
Shares the cool bias of Brass, Gold-tone, Chrome, Stainless steel and Copper, so they agree about the temperature of the room, and 48–61 points of lightness keep them readable as separate from this colour.
Black metal
needs care
Sits close to Black metal without matching it (ΔE00 18) — near enough that the eye reads an attempted match and far enough that it fails. Either move decisively away or repeat the tone exactly.
Metal carries more attention than its area suggests, so repetition matters more than the exact finish. More on metals and mixing them
Where it can go wrong
May read as simply dark rather than as its own colour. Below about L*22 the eye stops distinguishing hue reliably in ordinary room light, so this needs good lighting to be seen as anything but black.
Calculated directional adjustments. Some directions converge on the same result from this starting colour — shown as one merged card with an explanation, not repeated duplicates. Generated shades link to a curated profile only when one is close enough.
