#F3FA21

sRGB: 243 / 250 / 33

Cosmic tempests wander through twilight
Unbridled forces awaken beneath celestial skies
Distant echoes surrender to silence

#F3FA21 belongs to the yellow family. Its hex code tells a screen to mix 243 red, 250 green and 33 blue on a scale of 0 to 255. On the HSL wheel, hue is a position around a circle: 61.9° lands in the yellow region. Its 95.6% saturation makes it strong in color at this lightness. HSL lightness is 55.5% on a scale from black (0%) to white (100%). Of black and white lettering, black has the clearer light-to-dark separation on this background (18.51:1), which helps the shapes of letters stand out.

Color conversions

sRGB (8-bit): 243, 250, 33
HSL: 61.94°, 95.59%, 55.49%
HSV / HSB: 61.94°, 86.80%, 98.04%
CMYK (approx.): 2.80%, 0.00%, 86.80%, 1.96%
CIE XYZ (D65, Y = 100 for white): 71.420, 87.536, 14.573
CIELAB (D65, 2° observer): 94.965, -23.730, 89.023
WCAG relative luminance: 0.87536
24-bit decimal: 15989281

CMYK uses a profile-free approximation. Printed output depends on the press, ink and paper. Lab uses a D65 white point.

Text contrast

Contrast tells you how clearly lettering separates from #F3FA21 in light and dark. The ratio compares relative luminance, a measure of light weighted for human vision. Identical colors give 1:1 and black against white gives 21:1. A ratio of 2.99:1 falls just below the 3:1 AA minimum for large text. Body text needs at least 4.5:1 because its finer strokes are harder to distinguish.

Black text: 18.51:1

Normal text: AAA
Large text: AAA

White text: 1.13:1

Normal text: Fail
Large text: Fail

AA and AAA are WCAG accessibility levels. AAA sets a higher bar: 7:1 for normal text and 4.5:1 for large text. Large text begins at 18 pt regular or 14 pt bold. Ratings use the unrounded ratio.

Reference: WCAG text contrast guidance

Palettes & scales

Harmonies rotate the hue. Scales mix the starting color with white, black or middle gray in 20% steps in encoded sRGB.

Complementary

#2821FA sits half a turn (180°) from #F3FA21 on the HSL wheel. Keeping saturation and lightness steady while crossing to the opposite hue gives you a contrasting accent. Check text contrast separately before using the pair for lettering.

#F3FA21 #2821FA

Analogous

#FA9521 and #87FA21 sit 30° to either side of #F3FA21. The three hues are neighbors on the wheel, so you can change the color of a border or highlight while keeping it close to the original.

#FA9521 #F3FA21 #87FA21

Triadic

#F3FA21, #21F3FA and #FA21F3 are spaced 120° apart, forming a triangle on the wheel. Try one for the main color and the other two for accents.

#F3FA21 #21F3FA #FA21F3

Split complementary

Start at #F3FA21 and look across the wheel. #2186FA and #9521FA sit 30° to either side of its exact opposite, giving you two different accent choices.

#F3FA21 #2186FA #9521FA

Square

Starting with #F3FA21, each quarter turn (90°) takes you to the next hue: #21FA94, #2821FA, then #FA2186. Across the square, #F3FA21 pairs with #2821FA, and #21FA94 with #FA2186.

#F3FA21 #21FA94 #2821FA #FA2186

Tetradic

#F3FA21 and #2821FA are opposites, as are #21FA28 and #FA21F3. Together they form a rectangle on the wheel, with alternating gaps of 60° and 120°.

#F3FA21 #21FA28 #2821FA #FA21F3

Tints

Mixing #F3FA21 with white in 20% steps produces this scale. The first mixture, #F5FB4D, keeps 80% of the original. By #FDFED3, the mixture is 80% white.

#F3FA21 #F5FB4D #F8FC7A #FAFDA6 #FDFED3 #FFFFFF

Shades

Mixing #F3FA21 with black in 20% steps produces this scale. The first mixture, #C2C81A, keeps 80% of the original. By #313207, the mixture is 80% black.

#F3FA21 #C2C81A #929614 #61640D #313207 #000000

Tones

Mixing #F3FA21 with middle gray in 20% steps produces this scale. The first mixture, #DCE234, keeps 80% of the original. By #97986D, the mixture is 80% middle gray.

#F3FA21 #DCE234 #C5C947 #AEB15A #97986D #808080

Copy color codes

Hex, RGB and HSL are three ways to write this screen color. Paste any of them into a CSS color property.

Hex

#F3FA21

RGB

rgb(243 250 33)

HSL

hsl(61.935 95.595% 55.490%)

CSS example

.color-sample {
  background-color: #F3FA21;
  color: #000000;
}

Channel breakdown

RGB

#F3FA21 uses 243 red, 250 green and 33 blue. Each bar shows how much of that channel’s 0–255 range the screen uses.

Red 95.3%

Green 98.0%

Blue 12.9%

CMYK

A simple CMYK estimate for #F3FA21 is 2.8% cyan, 0.0% magenta, 86.8% yellow and 2.0% black. These are ink amounts; a printer profile is needed to predict the result on paper.

Cyan 2.8%

Magenta 0.0%

Yellow 86.8%

Black 2.0%

Nearby colors

The nearest shorthand match is #EEFF22. Its matching digit pairs let you write it as #EF2 in CSS. For a modern design, keep #F3FA21 when you want an exact match. Use its web-safe neighbor, #FFFF33, when matching a legacy palette of 216 colors.

Nearest shorthand: #EEFF22 Nearest web-safe: #FFFF33

Gradient to complement

#F3FA21 #D1D645 #AFB269 #8E8E8E #6C69B2 #4A45D6 #2821FA

Color vision previews

Compare how #F3FA21 appears in each simulation. When two chart lines or status indicators become hard to tell apart, a label, shape or line pattern gives readers another way to distinguish them. Individual perception varies.

Protanopia

A red–green color vision deficiency. Without a distinct response from long-wavelength cones, some reds and greens can look alike, and reds can appear darker.

#FFEE00

Deuteranopia

A red–green color vision deficiency. Without a distinct response from medium-wavelength cones, some greens can be difficult to distinguish from reds or browns.

#FFF33C

Tritanopia

A blue–yellow color vision deficiency. Without a distinct response from short-wavelength cones, blue can resemble green, and yellow can resemble pink.

#FFEAD6

Protanomaly (50%)

An altered long-wavelength cone response can make reds appear dimmer and harder to distinguish from greens. This swatch shows the model’s halfway setting.

#FFF300

Deuteranomaly (50%)

An altered medium-wavelength cone response can reduce the visible difference between reds and greens. This swatch shows the model’s halfway setting.

#FFF532

Tritanomaly (50%)

An altered short-wavelength cone response can make blue harder to distinguish from green. This swatch shows the model’s halfway setting.

#F8F58A

Grayscale (luminance)

This design check removes hue and preserves relative luminance so you can compare light and dark areas.

#F0F0F0

Partial grayscale (50% blend)

This design check mixes the original color halfway toward its grayscale equivalent in linear light. Use it to see how a design holds up as color fades.

#F2F5B2

Reference: National Eye Institute: Types of Color Vision Deficiency

Technical reference

CAM16 and CIECAM02 below assume D65 white, an average surround, background Y of 20 against white at 100, and adapting luminance of 4.07 cd/m².

Linear sRGB

These channels scale with emitted light. Use them for lighting calculations and physically meaningful blends.

R 0.89627 G 0.95597 B 0.01521

Display P3

P3 displays can reproduce a wider range of reds and greens. These coordinates reproduce this same sRGB swatch on a color-managed P3 display.

R 0.95789 G 0.97950 B 0.34643

Linear Display P3

These P3 channels are proportional to light, before display encoding.

R 0.90687 G 0.95399 B 0.09837

CIE xyY

The x and y coordinates locate chromaticity on a diagram. Y gives relative luminance on a scale where white is 100.

x 0.412 y 0.504 Y 87.536

CMY

Ideal cyan, magenta and yellow are the complements of the encoded red, green and blue channels.

C % 4.706 M % 1.961 Y % 87.059

Binary RGB

Each eight-bit group represents one channel. Together they store the 24-bit hex color.

11110011 11111010 00100001