BLUES

Dark Horizon

#666699

RGB 102, 102, 153 · HSL 240°, 20%, 50% · CMYK 33, 33, 0, 40

Dark Horizon is #666699 in HEX — rgb(102, 102, 153), hsl(240°, 20%, 50%), cmyk(33%, 33%, 0%, 40%).

Dark Horizon pulls into the mid-tone end of the blues spectrum — HSL 240°, 20%, 50%. The muted saturation makes it quiet but present, 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#666699

RGB102, 102, 153

HSL240°, 20%, 50%

HSV240°, 33%, 60%

CMYK33, 33, 0, 40

Decimal6710937

CSS RGBrgb(102, 102, 153)

CSS HSLhsl(240, 20%, 50%)

Paint Matches — this color across 16 brands

Behr

Peruvian Violet 660F-6

ΔE 2.7 · #6A6C9D

Vista Paint

Purple Spire C-1248

ΔE 3.8 · #706C9B

Sherwin-Williams

Forget‐Me‐Not SW6824

ΔE 3.9 · #716998

Kilz

Grape Beginnings RB130-02

ΔE 3.9 · #586194

Dulux

Kimberlite S42F6

ΔE 4.7 · #6971A5

Valspar

Purple Frenzy 4004-10C

ΔE 4.7 · #61619B

Hallman-Lindsay

Purple Spire 1249

ΔE 5.2 · #746F9D

Benjamin Moore

Bistro 1421

ΔE 5.9 · #54598B

PPG

Reign Over Me 1248-7

ΔE 6 · #76679E

Dunn-Edwards

Concord Jam DE5964

ΔE 8.9 · #695A82

Kobra

Violet 25

ΔE 9.2 · #776BAB

RAL

Pearl Violet 4011

ΔE 9.8 · #8673A1

Farrow & Ball

Pitch Blue 220

ΔE 12 · #636E8F

IKEA

IKEA128 128

ΔE 12.4 · #4A72B0

Dutch Boy

Blue Sea VS-9451

ΔE 18.5 · #2D61AD

Colorhouse

Petal .05 Petal-05

ΔE 21.2 · #1F4992

Light Reflectance & Undertone

Light Reflectance Value (LRV)

15/100

Dark

0 · DarkLight · 100

Soaks up light and feels moody and intimate. Great for studies, dining rooms and accent walls; pair with ample lighting.

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

#666699

#999966

Analogous

#667F99

#666699

#7F6699

Triadic

#666699

#996666

#669966

Split-Complementary

#666699

#998066

#809966

Tetradic

#666699

#996680

#999966

#669980

Monochromatic

#29293D

#47476B

#666699

#9494B8

#C2C2D6

Rectangle

#666699

#996699

#999966

#669966

Compound

#666699

#7F6699

#999966

#809966

Variations

Lighter

#8585AD

#A5A5C0

#CCCCD9

Darker

#51517B

#373756

#1F1F32

Saturation

#787887

#666699

#3333CC

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

5.35:1

vs Black

3.93:1

AA Large

Deuteranopia

#666699

#5B6C99

Original → Simulated

Protanopia

#666699

#666694

Original → Simulated

Tritanopia

#666699

#60706A

Original → Simulated

Color Psychology

Focused · Cooling

Dark Horizon 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

#8C798E

Warm Bulb 2700K

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

#666699

Daylight 5500K

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

#797EB2

Cool Bulb 6500K

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

Pairs With

#EAEAEB

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.

#878751

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 · Trim · Soft furniture

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: #666699;

CSS — background

background-color: #666699;

CSS Variable

--color-dark-horizon: #666699;

Tailwind v3 — config

colors: { 'dark-horizon': '#666699' }

Tailwind — arbitrary

bg-[#666699] text-[#666699]

SCSS

$dark-horizon: #666699;

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#53588A · ΔE 6.3

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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 #666699?

#666699 is Dark Horizon, a mid-tone blue with a cool undertone.

Is #666699 warm or cool?

Dark Horizon reads cool, which influences how it interacts with surrounding tones and natural light.

What rooms work best with Dark Horizon?

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

What colors pair well with Dark Horizon?

Dark Horizon 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 Dark Horizon?

You can download Dark Horizon 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 Dark Horizon?

The hex code is #666699. In RGB it's 102, 102, 153, and in HSL it's 240°, 20%, 50%.

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