CSS named color · RAL Classic color

Yellow #FFFF00

The CSS keyword yellow is #FFFF00. It is also the usual sRGB approximation of RAL 1026 Luminous yellow. It is a pale vivid yellow in the yellow family. In OKLCH it sits at lightness 0.968, chroma 0.211 and hue 109.8°.

Relative luminance
0.9278
OKLCH L · C · h
0.968 · 0.211 · 109.8
Best text
Black 19.55:1
Hue family
Yellow
Inspect this color Check contrast

#FFFF00 color codes

HEX
#FFFF00
RGB
rgb(255, 255, 0)
HSL
hsl(60, 100%, 50%)
OKLCH
oklch(0.968 0.211 109.8)
OKLab
oklab(0.968 -0.071 0.199)
CIELAB (D65)
L* 97.14, a* -21.55, b* 94.48
XYZ (D65)
X 77.00, Y 92.78, Z 13.85
CMYK (naive)
cmyk(0%, 0%, 100%, 0%)

CIELAB and XYZ use the D65 white point; CSS lab() uses D50, so paste the OKLCH or HEX value into stylesheets. CMYK here is a plain formula with no press profile.

RAL and RAL Classic are trademarks of RAL gGmbH, which this site is not affiliated with. The sRGB value is an approximation of the printed swatch; check a physical RAL color card before you specify a paint.

Legibility

Contrast: is #FFFF00 accessible?

Black text on it reaches 19.55:1, passing AAA. White text fails at 1.07:1.

WCAG 2 gives the same ratio whichever color is the text; APCA does not, so its Lc changes sign and size with polarity.

Open the Contrast System

  • Black text on it

    19.55:1

    • AA passes
    • AA large passes
    • AAA passes
    • APCA Lc +101

  • White text on it

    1.07:1

    • AA fails
    • AA large fails
    • AAA fails
    • APCA Lc 0

    Text is here, unreadable at 1.07:1

  • As text on black

    19.55:1

    • AA passes
    • AA large passes
    • AAA passes
    • APCA Lc −102

  • As text on white

    1.07:1

    • AA fails
    • AA large fails
    • AAA fails
    • APCA Lc 0

    Text is here, unreadable at 1.07:1

Nearest versions that pass 4.5:1

  • For text on white

    #797900 4.61:1

    Darkening its OKLCH lightness from 0.97 to 0.56 reaches 4.61:1 on white, keeping the hue.

    Compare both in the Contrast System

  • For text on black

    #FFFF00 19.55:1

    It already reaches 19.55:1 on black, so no change is needed.

Checking another pair? Use the Contrast Checker.

Studio

Adjust #FFFF00 live

Move lightness, chroma and hue in OKLCH, or drag on the map. The map is every lightness and chroma at the current hue: sRGB inside the solid area, Display P3 out to the dashed line.

The studio needs JavaScript.

Scale

Shades and tints of #FFFF00

Eleven OKLCH lightness steps at this hue, each with its contrast against white and black. #FFFF00 sits at step 50.

  1. 50This color#FFFF00
    White
    1.07
    Black
    19.55
  2. 100#F3F557
    White
    1.16
    Black
    18.00
  3. 200#E0E122
    White
    1.40
    Black
    14.96
  4. 300#C6C600
    White
    1.82
    Black
    11.47
  5. 400#A9A900
    White
    2.51
    Black
    8.36
  6. 500#8C8C00
    White
    3.57
    Black
    5.86
  7. 600#747400
    White
    4.95
    Black
    4.24
  8. 700#5C5C00
    White
    7.03
    Black
    2.98
  9. 800#434300
    White
    10.28
    Black
    2.04
  10. 900#2B2B00
    White
    14.50
    Black
    1.44
  11. 950#171700
    White
    18.11
    Black
    1.15

Under each step, white and black text on it; a bold figure passes 4.5:1.

Gamut

How vivid #FFFF00 can get

At its lightness and hue, sRGB reaches OKLCH chroma 0.211; #FFFF00 uses 100% of it. Display P3 reaches no further at this hue.

0.00.20.40.60.80.20.40.60.8 460480500520540560580600620
  • sRGB
  • Display P3
  • Rec. 2020
  • Dominant wavelength
OKLCH chroma
0.211
sRGB edge
0.211
Display P3 edge
0.211
Rec. 2020 edge
0.252
Dominant wavelength
570 nm
Excitation purity
79%
Chromaticity
x 0.4193, y 0.5052
  • This color#FFFF00
  • Most vivid in sRGB#FFFF00
  • Most vivid in Display P3oklch(0.968 0.211 109.8)

On a screen without Display P3 the last tile shows the sRGB edge instead.

Use the wider color where screens show it
.accent {
  color: #ffff00;
}
@media (color-gamut: p3) {
  .accent { color: color(display-p3 1 1 0.3311); }
}

Mixing

Mixing #FFFF00

Each row is the same mix worked out in a different space, with the halfway color at its end. sRGB, which older CSS gradients use, can sag gray or dark in the middle; OKLab keeps the lightness steps even; OKLCH holds chroma and hue as it goes.

White #FFFFFF

  • sRGB50%#FFFF80
  • OKLab50%#FEFFAC
  • OKLCH50%#FCFFC4

Black #000000

  • sRGB50%#808000
  • OKLab50%#636300
  • OKLCH50%#636300

Its complement #F4F3FF

  • sRGB50%#FAF980
  • OKLab50%#F8FBAE
  • OKLCH50%#FFF1F0
In CSS
/* A gradient and a mix, worked out in OKLCH */
background: linear-gradient(in oklch, #ffff00, white);
color: color-mix(in oklch, #ffff00 50%, white);

In use

#FFFF00 in an interface

A button, a link, a heading, a focused field, an icon and a chart line in this color, on a light page and a dark one. Each check is a WCAG 2 contrast minimum: 1.4.3 for text, 1.4.11 for the rest.

Light page

  • Button labelText, 4.5:119.55:1 Passes
  • Link and body-size textText, 4.5:11.07:1 Fails
  • Large headingLarge text, 3:11.07:1 Fails
  • Icons, borders and focus ringsNon-text, 3:11.07:1 Fails

For text on this page, the nearest shade that passes is #797900 4.61:1

Dark page

  • Button labelText, 4.5:119.55:1 Passes
  • Link and body-size textText, 4.5:117.44:1 Passes
  • Large headingLarge text, 3:117.44:1 Passes
  • Icons, borders and focus ringsNon-text, 3:117.44:1 Passes

Color vision

How #FFFF00 looks with color blindness

Achromatopsia changes it most, ΔE2000 30.5; deuteranopia changes it least, 1.8.

Simulated with Machado et al. (2009) at full severity, in linear light.

Simulate a whole page What each type sees

  • Protanopia

    No working red (long-wavelength) cones

    #FFF400 ΔE2000 2.9

    Close match

    Reads as pale vivid yellow

  • Deuteranopia

    No working green (medium-wavelength) cones

    #FFFA31 ΔE2000 1.8

    Very close

    Reads as pale vivid yellow

  • Tritanopia

    No working blue (short-wavelength) cones

    #FFEED9 ΔE2000 26.2

    Distinct

    Reads as pale grayish orange

  • Achromatopsia

    No cone color vision; lightness only

    #F7F7F7 ΔE2000 30.5

    Distinct

    Reads as off-white

Pairing check

Checked against its complement, #F4F3FF. Their lightness contrast is only 1.02:1, so where hue collapses, add a label, icon or pattern.

VisionThe pairΔE2000Verdict
Normal vision#FFFF00 · #F4F3FF38.9Stays distinct
Protanopia#FFF400 · #F1F4FF37.0Stays distinct
Deuteranopia#FFFA31 · #F1F4FF37.9Stays distinct
Tritanopia#FFEED9 · #F2F5F711.5Stays distinct
Achromatopsia#F7F7F7 · #F4F4F40.6Easily confused

Harmony

Color harmonies for #FFFF00

Its complement is #F4F3FF, an off-white.

Hue rotations in OKLCH, mapped into sRGB by trimming chroma so hue and lightness stay put.

Open the Harmony Studio
  • Base#FFFF00
  • Complement#F4F3FF

Complementary

Open in Harmony Studio
  • −30°#FFF3DF
  • Base#FFFF00
  • +30°#E0FFD9

Analogous

Open in Harmony Studio
  • Base#FFFF00
  • +120°#E8F7FF
  • +240°#FFF0F6

Triadic

Open in Harmony Studio
  • Base#FFFF00
  • +150°#EFF5FF
  • +210°#FCF0FF

Split-complementary

Open in Harmony Studio

Code

Design tokens

Ready-to-paste tokens in six formats. Rename them to fit your system.

CSS custom property

:root {
  --color-yellow: #ffff00;
}

Tailwind config

// tailwind.config.js
module.exports = {
  theme: {
    extend: {
      colors: {
        yellow: '#ffff00',
      },
    },
  },
};

Tailwind v4 theme

/* app.css — Tailwind CSS v4 */
@import "tailwindcss";

@theme {
  --color-yellow: oklch(0.968 0.211 109.8);
}

Design token (W3C DTCG)

{
  "color": {
    "yellow": {
      "$type": "color",
      "$value": {
        "colorSpace": "srgb",
        "components": [1, 1, 0],
        "hex": "#ffff00"
      },
      "$description": "CSS named color yellow"
    }
  }
}

SwiftUI color

import SwiftUI

enum Palette {
    static let yellow = Color(.sRGB, red: 1.000, green: 1.000, blue: 0.000, opacity: 1)
}

Jetpack Compose color

import androidx.compose.ui.graphics.Color

object Palette {
    val Yellow = Color(0xFFFFFF00)
}

Matches

The nearest match in each system

The closest CSS name, Tailwind shade, RAL Classic paint and Crayola crayon by ΔE2000; under 2 is hard to tell apart side by side. RAL and Crayola values approximate physical colors.

Neighbors

The eight nearest colors on this site by ΔE2000, closest first. Under 2 is hard to tell apart side by side.

Tools

Open #FFFF00 in the tools

Each opens over this page. More colors live in the Color Library, and every color page is listed on the hub.