CSS named colour

Indigo

#4b0082

A CSS named colour: indigo is valid anywhere a colour is expected.

RGB: rgb(75 0 130)
HSL: 275°, 100%, 25%
OKLCh: 33.9% 0.179 301.7

Indigo in every format

Web & CSSThe everyday formats for stylesheets and design tools.

Hex	`#4b0082`
RGB	`rgb(75 0 130)`
RGB legacy	`rgb(75, 0, 130)`
RGB percent	`rgb(29.41% 0% 50.98%)`
HSL	`hsl(274.6 100% 25.5%)`
HSL legacy	`hsl(274.6, 100%, 25.5%)`
HSV / HSB	`hsv(274.6, 100%, 51%)`
HWB	`hwb(274.6 0% 49%)`
Nearest name	`indigo`
CMYK	`cmyk(42.3%, 100%, 0%, 49%)`Naive conversion. Real print work needs an ICC profile.

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

OKLCh	`oklch(33.898% 0.17927 301.685)`Modern CSS colour space for even palettes — better than HSL when building scales.
OKLab	`oklab(33.898% 0.09416 -0.15255)`
CIE LCh	`lch(19.715% 71.818 310.907)`
CIE Lab	`lab(19.715% 47.029 -54.278)`
Display P3	`color(display-p3 0.2668 0.0302 0.4895)`
Rec. 2020	`color(rec2020 0.1958 0.0333 0.4348)`
srgb-linear	`color(srgb-linear 0.0704 0 0.2232)`Light-linear sRGB — the same numbers a shader wants for maths.
CIE XYZ (D65)	`color(xyz-d65 0.0693 0.0311 0.2135)`

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

GLSL vec3 — sRGB	`vec3(0.294, 0.0, 0.51)`Encoded values. Use when writing straight to the framebuffer.
GLSL vec3 — linear	`vec3(0.07, 0.0, 0.223)`Light-linear values. Use for lighting, blending and mixing.
GLSL vec4 — sRGB	`vec4(0.294, 0.0, 0.51, 1.0)`
GLSL vec4 — linear	`vec4(0.07, 0.0, 0.223, 1.0)`
GLSL ivec3	`ivec3(75, 0, 130)`
HLSL float3 — sRGB	`float3(0.294, 0.0, 0.51)`
HLSL float3 — linear	`float3(0.07, 0.0, 0.223)`
HLSL float4 — sRGB	`float4(0.294, 0.0, 0.51, 1.0)`
HLSL half4 — sRGB	`half4(0.294, 0.0, 0.51, 1.0)`
WGSL vec3f — sRGB	`vec3f(0.294, 0.0, 0.51)`
WGSL vec4f — sRGB	`vec4f(0.294, 0.0, 0.51, 1.0)`
WGSL vec3<f32> — linear	`vec3<f32>(0.07, 0.0, 0.223)`

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

Unity Color	`new Color(0.294f, 0.0f, 0.51f, 1.0f)`Color for everyday scripting (0–1). Color32 when you need whole numbers from 0 to 255.
Unity Color32	`new Color32(75, 0, 130, 255)`
Unreal FLinearColor	`FLinearColor(0.0704f, 0.0f, 0.2232f, 1.0f)`FLinearColor for materials and lighting. FColor when you need whole numbers from 0 to 255.
Unreal FColor	`FColor(75, 0, 130, 255)`Whole numbers from 0 to 255 — use when an API asks for FColor, not FLinearColor.
Godot Color	`Color(0.294, 0, 0.51, 1)`
Flutter Color	`Color(0xFF4B0082)`Packed ARGB, so alpha comes first.
Android Color	`Color.rgb(75, 0, 130)`
SwiftUI Color	`Color(red: 0.294, green: 0, blue: 0.51)`
UIKit UIColor	`UIColor(red: 0.294, green: 0, blue: 0.51, alpha: 1)`

Raw valuesPacked integers and plain arrays.

0x hex	`0x4B0082`
0x hex (ARGB)	`0xFF4B0082`
Array 0–1	`[0.294, 0, 0.51]`
Array 0–255	`[75, 0, 130]`
Decimal integer	`4915330`

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
Indigo on white	12.95:1	AAA	Lc 97	Body text at any size
Indigo on black	1.62:1	Fail	Lc 0	Not usable for text

Indigo text on a white background

Indigo text on a black background

White text on Indigo

Black text on Indigo

Tonal scale

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

50#fcf2ff
100#f4e6ff
200#e6cfff
300#d5b1ff
400#be8bff
500#a06be4
600#8551c5
700#6d3ca6
800#582a8b
900#471b73
950#2b034d

Tints and shades

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

Tint 1#653a99
Tint 2#8162ae
Tint 3#9f88c3
Tint 4#beafd8
Tint 5#ded6ec
Shade 1#390065
Shade 2#280049
Shade 3#17002f
Shade 4#090016
Shade 5#010003

Colours that work with Indigo

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

#303f00
#5a2800
#00453b
#1f1f92
#65005e

Closest CSS names

indigoexact match
midnightblueΔEok 0.101
darkslateblueΔEok 0.101
rebeccapurpleΔEok 0.103
purpleΔEok 0.120
darkblueΔEok 0.134