Dark Blue-gray

HEX: #666699 | Modern Palette

On White
5.35:1
PASS
On Black
3.93:1
FAIL

Color Specifications

HEX
#666699
RGB
102, 102, 153
HSL
240°, 33% ,60%
CMYK
33.33, 33.33, 0, 40

About Dark Blue-gray

Dark Blue-gray (#666699) is a color with RGB(102, 102, 153) and HSL(240°, 33.33%, 60%). It is commonly associated with Calm moods. In design, it fits Muted, Cool styles and is suitable for Text, Print. Its complementary color is #999966, which creates strong contrast. Its triadic palette includes Copper Rose (#996666) and #669966.

  • HEX: #666699
  • RGB: 102, 102, 153
  • HSL: 240°, 33.33%, 60%
  • Mood: Calm
  • Style: Muted, Cool
  • Use case: Text, Print
  • Complementary color: #999966
  • Triadic colors: Copper Rose (#996666), #669966

Live Components

LIGHT
DARK
System Notification Box

Color Palettes

Dark Blue-gray #666699 is used in Monochromatic, Neutral + Accent, Analogous, 3 + 1 + 1 palettes, giving designers ready-made combinations for backgrounds, surfaces, accents, and interface elements.

Monochromatic Five tones of the same hue — a reliable scale for backgrounds, surfaces, and text.
 
 
DARK BLUE-GRAY
 
 
Neutral + Accent Four near-neutral tones grounded by a saturated accent — clean and versatile for UI.
 
 
DARK BLUE-GRAY
 
 
Analogous Five hues drifting across a 60° arc — naturally harmonious and pleasing to the eye.
 
 
DARK BLUE-GRAY
 
 
3 + 1 + 1 Three analogous base colors, one complementary accent, one dark anchor — bold yet balanced.
 
 
 
 
 

Color Harmonies

Dark Blue-gray #666699 pairs with #999966 as its complementary color, and Copper Rose (#996666) and #669966 in triadic combinations. These harmony relationships help create balanced color combinations for UI, branding, and design work.

Complementary

The color directly opposite on the color wheel — creates maximum contrast and vibrance.

DARK BLUE-GRAY
Analogous

Colors adjacent on the wheel — naturally harmonious and pleasing to the eye.

DARK BLUE-GRAY
Triadic

Three colors equally spaced 120° apart — bold, balanced, and visually rich.

DARK BLUE-GRAY
COPPER ROSE
Split-Complementary

Two colors flanking the complement — high contrast with less tension than full complementary.

DARK BLUE-GRAY
Tetradic (Square)

Four colors at 90° intervals — rich variety, best when one color dominates.

DARK BLUE-GRAY
Monochromatic

Shades and tints of the same hue — cohesive, elegant, and easy to work with.

DARK BLUE-GRAY

Shades & Tints

The shade and tint range for Dark Blue-gray #666699 moves from dark #0A0A0F tones through the base color to lighter #F0F0F5 tones, making it useful for depth, hierarchy, and background variation.

DARK BLUE-GRAY

Color Characteristics

Mood
Calm
Style
Muted Cool
Use case
Text Print

Accessibility Simulation

Deuteranopia #666699
Protanopia #666699
Tritanopia #5C6E6E
Achromatopsia #6B6B6B

Frequently Asked Questions

Dark Blue-gray (#666699) is a color with RGB(102, 102, 153) and HSL(240°, 33.33%, 60%).

#666699 pairs strongly with #999966 as its complementary color. It can also be used with neutral tones for balanced UI and design layouts.

#666699 is suitable for Text, Print and works well with Muted, Cool styles.

#666699 is commonly associated with Calm.

Similar Named Colors
UCLA Blue #536895 ΔE 6.03
Liberty #545AA7 ΔE 6.86
Toolbox #746CC0 ΔE 7.56
Rhythm #777696 ΔE 7.90

Code Snippets

/* Background */
.element {
    background-color: #666699;
}

/* Text */
.element {
    color: #666699;
}

/* Border */
.element {
    border: 1px solid #666699;
}

/* Linear gradient to complementary */
.element {
    background: linear-gradient(
        to right,
        #666699,
        #BBBB77
    );
}

/* Radial gradient */
.element {
    background: radial-gradient(
        circle,
        #666699,
        #BBBB77
    );
}

// SCSS variable
$dark-blue-gray: #666699;

// With RGB channels (useful for rgba() usage)
$dark-blue-gray-r: 102;
$dark-blue-gray-g: 102;
$dark-blue-gray-b: 153;

// Usage
.element {
    background-color: $dark-blue-gray;
    color: rgba($dark-blue-gray-r, $dark-blue-gray-g, $dark-blue-gray-b, 0.8);
}