CSS named colour

Cyan

#00ffff

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

RGB: rgb(0 255 255)
HSL: 180°, 100%, 50%
OKLCh: 90.5% 0.155 194.8

Cyan in every format

Web & CSSThe everyday formats for stylesheets and design tools.

Hex	`#00ffff`
RGB	`rgb(0 255 255)`
RGB legacy	`rgb(0, 255, 255)`
RGB percent	`rgb(0% 100% 100%)`
HSL	`hsl(180 100% 50%)`
HSL legacy	`hsl(180, 100%, 50%)`
HSV / HSB	`hsv(180, 100%, 100%)`
HWB	`hwb(180 0% 0%)`
Nearest name	`cyan`
CMYK	`cmyk(100%, 0%, 0%, 0%)`Naive conversion. Real print work needs an ICC profile.

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

OKLCh	`oklch(90.54% 0.15455 194.769)`Modern CSS colour space for even palettes — better than HSL when building scales.
OKLab	`oklab(90.54% -0.14944 -0.0394)`
CIE LCh	`lch(90.666% 52.82 196.455)`
CIE Lab	`lab(90.666% -50.657 -14.962)`
Display P3	`color(display-p3 0.4584 0.9853 0.9925)`
Rec. 2020	`color(rec2020 0.6057 0.9651 0.9919)`
srgb-linear	`color(srgb-linear 0 1 1)`Light-linear sRGB — the same numbers a shader wants for maths.
CIE XYZ (D65)	`color(xyz-d65 0.5381 0.7874 1.0697)`

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

GLSL vec3 — sRGB	`vec3(0.0, 1.0, 1.0)`Encoded values. Use when writing straight to the framebuffer.
GLSL vec3 — linear	`vec3(0.0, 1.0, 1.0)`Light-linear values. Use for lighting, blending and mixing.
GLSL vec4 — sRGB	`vec4(0.0, 1.0, 1.0, 1.0)`
GLSL vec4 — linear	`vec4(0.0, 1.0, 1.0, 1.0)`
GLSL ivec3	`ivec3(0, 255, 255)`
HLSL float3 — sRGB	`float3(0.0, 1.0, 1.0)`
HLSL float3 — linear	`float3(0.0, 1.0, 1.0)`
HLSL float4 — sRGB	`float4(0.0, 1.0, 1.0, 1.0)`
HLSL half4 — sRGB	`half4(0.0, 1.0, 1.0, 1.0)`
WGSL vec3f — sRGB	`vec3f(0.0, 1.0, 1.0)`
WGSL vec4f — sRGB	`vec4f(0.0, 1.0, 1.0, 1.0)`
WGSL vec3<f32> — linear	`vec3<f32>(0.0, 1.0, 1.0)`

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

Unity Color	`new Color(0.0f, 1.0f, 1.0f, 1.0f)`Color for everyday scripting (0–1). Color32 when you need whole numbers from 0 to 255.
Unity Color32	`new Color32(0, 255, 255, 255)`
Unreal FLinearColor	`FLinearColor(0.0f, 1.0f, 1.0f, 1.0f)`FLinearColor for materials and lighting. FColor when you need whole numbers from 0 to 255.
Unreal FColor	`FColor(0, 255, 255, 255)`Whole numbers from 0 to 255 — use when an API asks for FColor, not FLinearColor.
Godot Color	`Color(0, 1, 1, 1)`
Flutter Color	`Color(0xFF00FFFF)`Packed ARGB, so alpha comes first.
Android Color	`Color.rgb(0, 255, 255)`
SwiftUI Color	`Color(red: 0, green: 1, blue: 1)`
UIKit UIColor	`UIColor(red: 0, green: 1, blue: 1, alpha: 1)`

Raw valuesPacked integers and plain arrays.

0x hex	`0x00FFFF`
0x hex (ARGB)	`0xFF00FFFF`
Array 0–1	`[0, 1, 1]`
Array 0–255	`[0, 255, 255]`
Decimal integer	`65535`

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
Cyan on white	1.25:1	Fail	Lc 12	Not usable for text
Cyan on black	16.75:1	AAA	Lc 92	Body text at any size

Cyan text on a white background

Cyan text on a black background

White text on Cyan

Black text on Cyan

Tonal scale

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

50#c1ffff
100#80ffff
200#5bf7f6
300#12e1e1
400#00c4c5
500#00a2a3
600#008586
700#006b6c
800#005656
900#004444
950#002728

Tints and shades

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

Tint 1#66ffff
Tint 2#90ffff
Tint 3#b1ffff
Tint 4#cdffff
Tint 5#e7ffff
Shade 1#00c8c8
Shade 2#009494
Shade 3#006363
Shade 4#003636
Shade 5#000f0f

Colours that work with Cyan

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

#ffcdd1
#f8cdff
#ffd588
#67ffc6
#9cedff

Closest CSS names

cyanexact match
aquamarineΔEok 0.068
turquoiseΔEok 0.090
paleturquoiseΔEok 0.091
powderblueΔEok 0.110
lightblueΔEok 0.122