Color Details and Palettes for #637C88

Details about the color Night Owl

Closest web-safe match: #666699

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 #637C88
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About Color Hex #637c88

The color Night Owl, with hexadecimal code #637c88, belongs to the blue color family, the world's most universally preferred hue. Blue projects trust, stability, and intellectual calm, which is why it dominates corporate, financial, and technology branding worldwide. Additionally, it evokes emotions such as Softness, Delicacy, Calmness, Relaxation and Friendliness. Blue signifies tranquility and stability. In Middle Eastern cultures, it can also represent protection against the evil eye, while in Western cultures, it symbolizes calmness and reliability. At just 16% saturation, this near-neutral shade carries only a subtle hint of its underlying hue, making it versatile for large surfaces and professional contexts. With a mid-range lightness of 46%, it offers excellent versatility—readable as text on light backgrounds and visible as an element on dark ones. This color is ideal for designs that aim to express Softness, Delicacy, Calmness, Relaxation, or Friendliness. It can be effectively used in web design, branding, and marketing materials to attract attention and convey specific messages.

The RGB values for Night Owl are (99, 124, 136), providing a combination of red: 99, green: 124, and blue: 136. In HSL format, it has a hue of 199.00°, saturation of 16.00%, and lightness of 46.00%.

The HSV representation includes a hue of 199.00°, saturation of 27.00%, and value of 53.00%. Its CMYK composition is cyan: 27.00%, magenta: 9.00%, yellow: 0.00%, and black: 47.00%.

The calculated luminance of #637c88 is 0.188, offering a brightness level suitable for various design requirements.

This color is not part of the web-safe color palette. The closest web-safe color to this is the color HEX #666699. Its contrast ratio is 4.77:1 against black and 4.40:1 against white. It works well on dark backgrounds but may be less readable on lighter ones.

In terms of color temperature, #637c88 reads as cool. When it comes to accessibility, testing against standard guidelines suggests that using black text meets typical WCAG contrast standards. Additionally, the ideal foreground color for improved legibility on #637c88 is black.

Considering its saturation and lightness, #637c88 appears more vivid and energetic, making it stand out in designs that aim to capture attention.

History, Usage, Psychology & Design Ideas for #637C88

Night Owl (#637C88) belongs to the Azure color family.

With a dusty, low-saturation character, this color offers quiet complexity—neither bold nor faded. Dusty tones add vintage charm to retro-inspired designs and pair beautifully with metallic accents like copper or brass.

Historical Background

Azure derives from the Arabic lazaward, referring to the lapis lazuli stone that yielded ultramarine pigment—once more costly per ounce than gold. Medieval European painters reserved ultramarine for the most sacred subjects, particularly the Virgin Mary's robes. The word azure also entered heraldry as the term for blue fields on coats of arms, symbolizing loyalty and truth.

Design & Usage Tips

Azure strikes a balance between the brightness of cyan and the depth of blue, making it a versatile choice for technology, aviation, and financial brands (Microsoft Azure is a prominent example). Pair azure with white for authority and clarity, or with light gold for a regal combination.

Sitting on the cool side of the spectrum (hue 199°), it promotes a feeling of calm distance and intellectual clarity, which is why cool hues dominate corporate identities, healthcare design, and productivity tools. With only 16% saturation, this near-neutral shade carries just a hint of its underlying hue—subtle enough for large surfaces yet adding more warmth (or coolness) than a pure gray.

Psychological Impact

Azure evokes trust, aspiration, and openness—like a clear sky. It feels less corporate than navy and more refined than bright blue, hitting a sweet spot for brands that want to appear both professional and approachable.

With a mid-range lightness of 46%, this tone is highly versatile: dark enough to serve as body text on white, yet light enough to stand out on charcoal or navy backgrounds.

Creative Design Ideas

Use azure as the primary brand color with charcoal text for a clean SaaS identity. Create split-screen layouts with an azure panel on one side and white on the other for impactful above-the-fold sections. In icon design, azure provides excellent visibility against both light and dark backgrounds.

#637C88 Color Conversions

Every way to write Night Owl — copy Night Owl as RGB, HSL, HSV, HWB, CMYK, OKLCH, OKLab, CIELAB, LCH, XYZ or a decimal integer. One-tap copy on every format; tap on any card to learn what it is and when to use it.

12 formats
HEX Web
#637C88

Hexadecimal is the web’s universal color notation — two digits each for red, green and blue. Drop it straight into HTML, CSS or any design tool.

RGB Screen
rgb(99, 124, 136)

RGB is the additive Red-Green-Blue model every screen uses to emit light. The default choice for websites, apps and on-screen UI.

HSL Web
hsl(199, 16%, 46%)

HSL breaks a color into Hue, Saturation and Lightness — the most intuitive way to lighten, darken or mute a color in CSS.

HSV HSB Design
hsv(199, 27%, 53%)

HSV (also called HSB) maps Hue, Saturation and Value/Brightness. It is the model behind the color pickers in Photoshop, Figma and most design apps.

HWB CSS 4
hwb(199 39% 47%)

HWB blends a pure hue with Whiteness and Blackness — a painter-friendly model added in CSS Color 4 for quick tints and shades.

CMYK Print
cmyk(27%, 9%, 0%, 47%)

CMYK is the subtractive Cyan-Magenta-Yellow-Black ink model. Use these values when preparing artwork for a printer or commercial press.

OKLCH Modern
oklch(57.09% 0.034 228.68)

OKLCH is a modern, perceptually-uniform space (Lightness, Chroma, Hue). It powers smooth gradients and accessible palettes in today’s CSS.

OKLab Modern
oklab(57.09% -0.023 -0.026)

OKLab is the Cartesian form of OKLCH — ideal for blending and interpolating colors without the muddy midpoints older spaces produce.

CIELAB L*a*b* Perceptual
L: 50.51, a: -6.08, b: -9.49

CIELAB is a device-independent, perceptually-uniform space. It is the standard for measuring color difference (ΔE) and matching across devices.

LCH Perceptual
L: 50.51, C: 11.26, H: 237.36

LCH is CIELAB in cylindrical form — Lightness, Chroma and Hue — letting you adjust vividness and hue while staying perceptually even.

XYZ CIE Science
X: 16.80, Y: 18.85, Z: 26.04

CIE XYZ is the 1931 master space that underpins every other model here — the scientific bridge used to convert between color systems.

Decimal int Code
6519944

The 24-bit integer value of the color — handy for databases, APIs, game engines and low-level graphics code.

RGB Color Percentages for #637c88

RGB Color Percentages for Night Owl (HEX Code: #637c88) display the relative contribution of Red, Green, and Blue in forming the color. Understanding these percentages provides insight into the color's visual balance and primary components.

This color is primarily dominated by Blue, making up 37.88% of the total composition. The complete breakdown of RGB contributions is:

Red:
27.58%
Green:
34.54%
Blue:
37.88%

This analysis highlights the influence of each primary color, offering a deeper understanding of the visual characteristics of Night Owl.

CMYK Ink Levels & Print Guide for #637c88

CMYK Ink Levels for Night Owl (HEX Code: #637c88) provide a breakdown of the percentages of Cyan, Magenta, Yellow, and Black inks needed for accurate print reproduction. The composition of Night Owl prominently features Key, reflecting its dominant color characteristic. This information is invaluable for optimizing ink usage and achieving precise color results in printed materials.

The exact CMYK values are: Cyan: 27.21%, Magenta: 8.82%, Yellow: 0%, and Black: 46.67%.

Luminance & Contrast for #637C88

Relative luminance gauges how bright Night Owl is, while the WCAG contrast ratios show how legible black or white text is on it — and which accessibility levels (AA / AAA) it passes.

Relative luminance 0.188
0 · dark1 · light
Aa
Black text 4.77:1
AA AAA Large
Aa
White text 4.40:1
AA AAA Large

Quick CSS Snippets for #637C88

Copy-and-paste CSS for Night Owl — backgrounds, text, borders and a custom property. Each line is ready to drop into your stylesheet.

Background background-color: #637C88;
Text color: #637C88;
Border border: 2px solid #637C88;
RGB background-color: rgb(99, 124, 136);
HSL background-color: hsl(199, 16%, 46%);
Variable --color: #637C88;

#637c88 Monochrome Palette

The Monochrome Palette consists of shades created by adjusting the brightness. These include lighter, original, and darker shades of the color. This layout helps to visualize the color's range and its potential use in design.

#eff2f3
#d8dee1
#c1cbcf
#a9b7be
#92a3ac
#7a909a
#637c88 Original
#546974
#45575f
#36444b
#283236
#191f22
#0a0c0e

#637c88 Complementary Palette

The Complementary Palette is made up of two colors that sit opposite each other on the color wheel. These colors create high contrast and vibrant designs, making them perfect for attention-grabbing elements and dynamic visuals.

#637c88 Original
#886e63

#637c88 Analogic Palette

The Analogic Palette consists of colors that are next to each other on the color wheel. These colors typically create harmonious and subtle designs, often used to evoke calmness and unity in your visual projects.

#637c88 Original
#636988
#638881
#6e6388
#63886e
#816388
#698863

#637c88 Triadic Palette

The Triadic Palette is made up of three colors evenly spaced on the color wheel. This combination provides a vibrant and balanced color scheme, often used for dynamic and energetic designs while maintaining harmony.

#637c88 Original
#88637c
#7c8863

#637c88 Quad Palette

The Quad Palette, also known as tetradic, consists of four colors evenly spaced on the color wheel. This combination offers a diverse and bold color scheme, ideal for creating rich, complex designs with multiple accents while still maintaining balance.

#637c88 Original
#816388
#886e63
#698863

Color Blindness Simulation for #637c88

Colors are perceived differently by individuals with various forms of color blindness. Use the dropdown below to see how this color may look through the eyes of someone with color vision deficiency. Explore how Night Owl (#637c88) might appear to people with different visual experiences, and gain deeper insights into color accessibility for your designs!

Each color box displays a "Friendly" or "Not Friendly" tag in the bottom-right corner. A "Friendly" tag indicates that the color difference is distinguishable to individuals with the specific type of color blindness. Conversely, a "Not Friendly" tag means that the color difference might not be distinguishable, potentially causing accessibility issues in your design.

Normal Vision

Deuteranopia (Green Weakness)

Friendly

Protanopia (Red Weakness)

Friendly

Tritanopia (Blue-Yellow Weakness)

Friendly

Achromatopsia (Total Color Blindness)

Friendly

Color Harmonies for #637c88

Color harmonies refer to the visually pleasing combinations of colors that are derived from specific relationships on the color wheel. These harmonious schemes, such as complementary, triadic, and analogous colors, create a balanced and engaging visual experience in design.

Complementary

Analogous

Triadic

Tetradic (Quad)

#637C88 Nearby Colors

A handful of colors just a step away from #637C88 — each one nudges the brightness, richness, or shade a little while still feeling like the same color. Use the buttons on any swatch to copy its hex or open its full color page.

#778899 Light Slate Gray
#556677 Midnight Shadow
#8899aa Blank Stare
#446666 Rosemary
#557799 Quiet Harbour
#777777 Lucky Grey
#667788 Plumbeous
#668899 Horizon

Colors Similar to #637c88

These colors are close neighbours of #637C88 in the RGB color space. Each subtle variation can produce a noticeably different mood in your design while remaining harmonious with the original Blue tone.

#647c88 Citadel
#637d88 Night Owl
#637c89 Night Owl
#627c88 Night Owl
#637b88 Night Owl
#637c87 Night Owl
#747c88 Nocturnal
#638d88 Yucca
#637c99 Bay View
#527c88 Hydro
#636b88 Dark Prince
#637c77 Underwater World

Looking for more Blue shades? Browse Blue colors →

Explore Vibrant Images Featuring Night Owl (#637c88)

Discover a vibrant gallery of images that not only showcase the captivating hue of Night Owl, but also embody its unique mood and personality. Each carefully curated photo is selected to highlight the richness and diversity of this color, offering inspiration for design, art, and creative projects.