BLUES

Duke Blue

#00009C

RGB 0, 0, 156 · HSL 240°, 100%, 31% · CMYK 100, 100, 0, 39

Duke Blue is #00009C in HEX — rgb(0, 0, 156), hsl(240°, 100%, 31%), cmyk(100%, 100%, 0%, 39%).

Duke Blue pulls into the rich end of the blues spectrum — HSL 240°, 100%, 31%. The saturated saturation makes it bold and immediate, and the hue reads cool. In interior projects it shines on bedrooms, bathrooms, home offices — for calm, focused environments. Reads best alongside warm white trim, oak or walnut, brass or matte black hardware.

Color Codes

HEX#00009C

RGB0, 0, 156

HSL240°, 100%, 31%

HSV240°, 100%, 61%

CMYK100, 100, 0, 39

Decimal156

CSS RGBrgb(0, 0, 156)

CSS HSLhsl(240, 100%, 31%)

Paint Matches — this color across 16 brands

Behr

Tanzanite P530-7

ΔE 17.9 · #1A32B6

Dutch Boy

Blue Royale VS-9550

ΔE 45.8 · #243F90

RAL

Signal Blue 5005

ΔE 51 · #1E2D6E

Colorhouse

Petal .05 Petal-05

ΔE 53.7 · #1F4992

Vista Paint

Iris Illusion K-24

ΔE 55.1 · #583E7B

PPG

Crushed Velvet 1245-7

ΔE 57.1 · #445397

Hallman-Lindsay

Blue Highlight 613

ΔE 57.4 · #324A8B

Benjamin Moore

Blue 2066-10

ΔE 58 · #243973

Dulux

Brilliant Purple SB8G8

ΔE 58.1 · #4D4985

Dunn-Edwards

Beaded Blue DE5909

ΔE 58.3 · #494D8B

Kilz

Superstition RH250

ΔE 63.1 · #604C7F

Valspar

Rollick 4003-10C

ΔE 63.1 · #745A92

Kobra

Violet 25

ΔE 63.3 · #776BAB

Sherwin-Williams

Fully Purple SW6983

ΔE 64.2 · #514C7E

IKEA

IKEA128 128

ΔE 69.4 · #4A72B0

Farrow & Ball

Pitch Blue 220

ΔE 80.6 · #636E8F

Light Reflectance & Undertone

Light Reflectance Value (LRV)

2/100

Very Dark

0 · DarkLight · 100

Absorbs almost all light — dramatic and cocooning. Needs strong artificial lighting and works best as an accent or in well-lit rooms.

Undertone

TemperatureCool MasstoneBlue UndertoneViolet

Reads as a cool blue with a violet undertone showing through, especially in daylight. Pair trim and adjacent colours to either calm or amplify that undertone.

Color Theory

Complementary

#00009C

#9E9E00

Analogous

#004F9E

#00009C

#4F009E

Triadic

#00009C

#9E0000

#009E00

Split-Complementary

#00009C

#9E4F00

#4F9E00

Tetradic

#00009C

#9E004F

#9E9E00

#009E4F

Monochromatic

#00001A

#000052

#00009C

#0000EB

#3838FF

Rectangle

#00009C

#9E009E

#9E9E00

#009E00

Compound

#00009C

#4F009E

#9E9E00

#4F9E00

Variations

Lighter

#0000E4

#3C3CEF

#9696ED

Darker

#00007E

#000057

#000033

Saturation

#373767

#00009E

Interior Use

Best Rooms

bedrooms, bathrooms, home offices

Best Uses

main walls, ceilings, trim, cabinetry

Pairs With

warm white trim, oak or walnut, brass or matte black hardware

Accessibility (WCAG)

vs White

14.19:1

AAA

vs Black

1.48:1

Fail

Deuteranopia

#00009C

#00309C

Original → Simulated

Protanopia

#00009C

#000092

Original → Simulated

Tritanopia

#00009C

#004127

Original → Simulated

Color Psychology

Focused · Cooling

Duke Blue lowers the temperature of a room — useful in south-facing rooms that overheat visually, and in home offices where you want a clear head. Pair with warm wood and brass to keep it from reading clinical.

SymbolismTrust, depth, stability

PersonalityClear-headed, dependable, contemplative

focustrustcalmofficebedroomdepth

How it looks under different light

#3F2D90

Warm Bulb 2700K

Incandescent / soft white LED — pulls colour toward yellow/amber.

#00009C

Daylight 5500K

Midday natural light or daylight-spec LED — closest to the paint chip.

#2D32B4

Cool Bulb 6500K

Cool white LED / overcast daylight — pulls colour toward blue.

Pairs With

#E7E7EE

Trim

Matched off-white

Same hue at 92% lightness — trim reads coordinated, not stark.

#F7F7F8

Ceiling

Whisper tint

Near-white with a hint of the hero's undertone — ceiling feels intentional.

#79790D

Accent

Complementary punch

Hue +180°, slightly muted for paint vs. screen — use on a door, frame, or single piece.

#574738

Floor

Walnut neutral

Warm mid-brown grounds the scheme regardless of hero hue.

Paint Info

Brand · Product Line

Benjamin Moore / Regal Select Interior

Recommended Finishes

Eggshell (walls) · Pearl (trim) · Matte (ceiling)

Eggshell hides imperfections on main walls while keeping the color rich; pearl on trim adds subtle sheen and easier cleaning; flat matte on ceilings prevents glare.

Best Surfaces

Primary walls · Cabinetry · Doors · Mouldings

Coverage & Dry Time

Typical coverage 350-400 sq ft per gallon over a primed surface.

Touch-dry in ~1 hour. Recoat after 4 hours. Full cure 7-14 days.

Primer

Standard primer is adequate.

Application Tip

Use a 9" microfiber roller on walls and a 2.5" angled sash brush for trim cuts. Two coats minimum for even depth.

Paint Calculator

Wall area (m²)

Coats

Coverage (m² / L)

You'll need

4.0 litres

1.06 US gallons · room for one touch-up coat. Buy slightly more to ensure single-batch match.

Code Snippets

CSS — color

color: #00009C;

CSS — background

background-color: #00009C;

CSS Variable

--color-duke-blue: #00009C;

Tailwind v3 — config

colors: { 'duke-blue': '#00009C' }

Tailwind — arbitrary

bg-[#00009C] text-[#00009C]

SCSS

$duke-blue: #00009C;

Similar Colors

Warriors Blue

#00498D · ΔE 57.8

Blue

#233872 · ΔE 57.8

Scandinavian Blue

#4E4E8C · ΔE 58.3

Mystical Grape

#664B86 · ΔE 58.6

Evening Blue

#004E93 · ΔE 58.6

Twilight Blue

#365496 · ΔE 59.5

Basic Blue

#3F457D · ΔE 60.3

Delphinium

#304C89 · ΔE 60.4

Built by DSGN.HOUSE Updated 2026

Our color tools run on our own catalogue of 26,000+ real paint colors across 16 brands — Benjamin Moore, Sherwin-Williams, Behr, Dulux, RAL and more — with the color math (HSL and CIELAB matching) computed in-house, not scraped from summaries. Every color you pick maps to a real, buyable paint with its code, so what you see here you can actually take to the store. We review and update these tools and their data regularly.

Created by Denis Kataev, founder of DSGN.HOUSE — a software engineer and digital entrepreneur building professional color-design tools for everyone.

Frequently Asked Questions

What color is #00009C?

#00009C is Duke Blue, a deep blue with a cool undertone.

Is #00009C warm or cool?

Duke Blue reads cool, which influences how it interacts with surrounding tones and natural light.

What rooms work best with Duke Blue?

Duke Blue works well in bedrooms, bathrooms, home offices. Designers typically use it for main walls, ceilings, trim, cabinetry.

What colors pair well with Duke Blue?

Duke Blue pairs naturally with warm white trim, oak or walnut, brass or matte black hardware. Its complementary color is also a strong contrast option for accents.

Where can I download Duke Blue?

You can download Duke Blue on DSGN.HOUSE in 15 designer formats including CSS gradient, Figma, Procreate swatches, Tailwind config, Adobe ASE, SVG, and 4K wallpapers — all free.

What's the hex code for Duke Blue?

The hex code is #00009C. In RGB it's 0, 0, 156, and in HSL it's 240°, 100%, 31%.

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