Colour reference

Slate Blue

#457b9d

RGB: rgb(69 123 157)
HSL: 203°, 39%, 44%
OKLCh: 56.0% 0.078 238.0

Slate Blue in every format

Web & CSSThe everyday formats for stylesheets and design tools.

Hex	`#457b9d`
RGB	`rgb(69 123 157)`
RGB legacy	`rgb(69, 123, 157)`
RGB percent	`rgb(27.06% 48.24% 61.57%)`
HSL	`hsl(203.2 38.9% 44.3%)`
HSL legacy	`hsl(203.2, 38.9%, 44.3%)`
HSV / HSB	`hsv(203.2, 56.1%, 61.6%)`
HWB	`hwb(203.2 27.1% 38.4%)`
Nearest name	`steelblue (approx.)`
CMYK	`cmyk(56.1%, 21.7%, 0%, 38.4%)`Naive conversion. Real print work needs an ICC profile.

Perceptual & wide gamutModern CSS colour spaces for uniform scales and P3 displays.

OKLCh	`oklch(55.981% 0.07814 237.982)`Modern CSS colour space for even palettes — better than HSL when building scales.
OKLab	`oklab(55.981% -0.04143 -0.06626)`
CIE LCh	`lch(48.967% 26.544 245.895)`
CIE Lab	`lab(48.967% -10.841 -24.23)`
Display P3	`color(display-p3 0.3211 0.4771 0.6032)`
Rec. 2020	`color(rec2020 0.3196 0.4215 0.5594)`
srgb-linear	`color(srgb-linear 0.0595 0.1981 0.3372)`Light-linear sRGB — the same numbers a shader wants for maths.
CIE XYZ (D65)	`color(xyz-d65 0.1562 0.1786 0.3452)`

ShadersGLSL, HLSL and WGSL vectors in both encoded and linear form.

GLSL vec3 — sRGB	`vec3(0.271, 0.482, 0.616)`Encoded values. Use when writing straight to the framebuffer.
GLSL vec3 — linear	`vec3(0.06, 0.198, 0.337)`Light-linear values. Use for lighting, blending and mixing.
GLSL vec4 — sRGB	`vec4(0.271, 0.482, 0.616, 1.0)`
GLSL vec4 — linear	`vec4(0.06, 0.198, 0.337, 1.0)`
GLSL ivec3	`ivec3(69, 123, 157)`
HLSL float3 — sRGB	`float3(0.271, 0.482, 0.616)`
HLSL float3 — linear	`float3(0.06, 0.198, 0.337)`
HLSL float4 — sRGB	`float4(0.271, 0.482, 0.616, 1.0)`
HLSL half4 — sRGB	`half4(0.271, 0.482, 0.616, 1.0)`
WGSL vec3f — sRGB	`vec3f(0.271, 0.482, 0.616)`
WGSL vec4f — sRGB	`vec4f(0.271, 0.482, 0.616, 1.0)`
WGSL vec3<f32> — linear	`vec3<f32>(0.06, 0.198, 0.337)`

Engines & appsConstructors for Unity, Unreal, Godot, Flutter, SwiftUI and Android.

Unity Color	`new Color(0.271f, 0.482f, 0.616f, 1.0f)`Color for everyday scripting (0–1). Color32 when you need whole numbers from 0 to 255.
Unity Color32	`new Color32(69, 123, 157, 255)`
Unreal FLinearColor	`FLinearColor(0.0595f, 0.1981f, 0.3372f, 1.0f)`FLinearColor for materials and lighting. FColor when you need whole numbers from 0 to 255.
Unreal FColor	`FColor(69, 123, 157, 255)`Whole numbers from 0 to 255 — use when an API asks for FColor, not FLinearColor.
Godot Color	`Color(0.271, 0.482, 0.616, 1)`
Flutter Color	`Color(0xFF457B9D)`Packed ARGB, so alpha comes first.
Android Color	`Color.rgb(69, 123, 157)`
SwiftUI Color	`Color(red: 0.271, green: 0.482, blue: 0.616)`
UIKit UIColor	`UIColor(red: 0.271, green: 0.482, blue: 0.616, alpha: 1)`

Raw valuesPacked integers and plain arrays.

0x hex	`0x457B9D`
0x hex (ARGB)	`0xFF457B9D`
Array 0–1	`[0.271, 0.482, 0.616]`
Array 0–255	`[69, 123, 157]`
Decimal integer	`4553629`

Contrast and accessibility

WCAG 2 ratios are what audits and legislation reference. APCA is shown alongside because WCAG 2 is known to misjudge mid-tone backgrounds, and it is the basis of the WCAG 3 draft.

Pairing	WCAG 2 ratio	Level	APCA	Suitable for
Slate Blue on white	4.59:1	AA	Lc 72	Headings and large text
Slate Blue on black	4.57:1	AA	Lc 30	Not usable for text

Slate Blue text on a white background

Slate Blue text on a black background

White text on Slate Blue

Black text on Slate Blue

Tonal scale

Hue held fixed while lightness walks OKLCh, ready to use as a design system ramp.

50#e2fcff
100#cef4ff
200#b5e3ff
300#9bcdef
400#7cb1d4
500#5c92b5
600#447899
700#30607e
800#204d67
900#123c54
950#012235

Tints and shades

Mixed perceptually toward white and black, so the steps feel evenly spaced.

Tint 1#6490ad
Tint 2#82a6be
Tint 3#a1bcce
Tint 4#c0d2de
Tint 5#dfe8ef
Shade 1#345f7a
Shade 2#244559
Shade 3#152c3a
Shade 4#07151d
Shade 5#010305

Colours that work with Slate Blue

Complementary, triadic and analogous partners, rotated in OKLCh so they keep the same apparent brightness.

#976945
#9a6174
#707b44
#31818c
#6173a3

Closest CSS names

steelblueΔEok 0.037
slategrayΔEok 0.058
tealΔEok 0.066
darkcyanΔEok 0.070
lightslategrayΔEok 0.075
dimgrayΔEok 0.087