Photo in the color Capri
Pictured: Capri, the closest color we have a photo of (#00BFFF)
rgb(4, 217, 255)
#04D9FF

Neon Blue #04D9FF RGB Color Code

Name from the community color list.

Neon Blue (#04D9FF) is a moderately saturated, light cyan. In RGB it is made of 2% red, 85% green and 100% blue (R 4, G 217, B 255). The blue channel is the strongest. In HSL it has a hue of 189Β°, 100% saturation and 51% lightness. Its relative luminance is 0.569, so black text is easier to read on top of it. For print, a rough CMYK match is 98% cyan, 15% magenta, 0% yellow and 0% black. Check it against your printer's ICC profile before you print. It is a cool color. It goes well with warm oranges and reds for contrast. For a calm, matching look, use nearby cool tones.

Open in color picker
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Neon Blue color codes

#04D9FF in every common color format. Click a value to copy it.

FormatValueNotesCopy
HEX #04D9FF Valid CSS
RGB rgb(4, 217, 255) Valid CSS
HSL hsl(189, 100%, 51%) Valid CSS
HSV / HSB hsv(189, 98%, 100%) Not a CSS format
HWB hwb(189 2% 0%) Valid CSS
CMYK cmyk(98%, 15%, 0%, 0%) Approximate (no ICC profile)
OKLCH oklch(81.61% 0.145 216.55) Valid CSS
OKLab oklab(81.61% -0.1165 -0.0864) Valid CSS
CIELAB lab(79.52% -35.48 -31.72) D50, as in CSS
CIELCH lch(79.52% 47.59 221.8) Valid CSS
Display P3 color(display-p3 0.3874 0.8383 0.9826) Valid CSS
XYZ (D65) color(xyz-d65 0.4291 0.5687 1.0333) Valid CSS
Decimal 317951 Integer (0xRRGGBB)

CMYK here is a rough screen match without an ICC profile. See CMYK and print. Relative luminance: 0.5687. Nearest web-safe color: #00CCFF.

Mix Neon Blue with other colors

See what #04D9FF makes with red paint, under a green light, printed with cyan ink and in a digital blend with blue. Click a picture to change the colors and amounts in the color mixer.

PaintNeon Blue and red paintOpen in the color mixer
LightNeon Blue and green lightOpen in the color mixer
PrintNeon Blue and cyan inkOpen in the color mixer
DigitalNeon Blue blended with blueOpen in the color mixer

Use Neon Blue in your code

Ready to paste into CSS, Sass, Tailwind, iOS, Android and Flutter. Click the icon to copy a line.

WhereCodeCopy
CSS variable--neon-blue: #04D9FF;
Sass variable$neon-blue: #04D9FF;
Tailwind CSS v4@theme { --color-neon-blue: #04D9FF; }
Tailwind CSS v3 configcolors: { 'neon-blue': '#04D9FF' }
SwiftUIColor(red: 0.016, green: 0.851, blue: 1)
UIKitUIColor(red: 0.016, green: 0.851, blue: 1, alpha: 1)
Android XML<color name="neon_blue">#FF04D9FF</color>
Flutter and Jetpack ComposeColor(0xFF04D9FF)

Accessibility and contrast

Black text works best on #04D9FF (12.37:1, AAA). Here is how #04D9FF does as a text color:

Large heading text
Body text at 16px. The quick brown fox jumps over the lazy dog.
1.70:1 on white
APCA Lc 30
Fails AATry #00829A
Large heading text
Body text at 16px. The quick brown fox jumps over the lazy dog.
12.37:1 on black
APCA Lc -73
AAA

Check this color against any background in the contrast checker. WCAG ratios and APCA Lc values measure different things, so one can't stand in for the other. Learn more.

How people with color blindness see Neon Blue

#04D9FF next to its complement and its two triadic colors, as seen with each type of color blindness.

  • Normal visionhow most people see it
  • Protanopiano red cones, about 1% of men
  • Deuteranopiano green cones, the most common type
  • Tritanopiano blue cones, very rare
  • Achromatopsiano color at all, very rare

#04D9FF stays easy to tell apart from its complement and triadic colors for the common types of color blindness. Try your own colors in the color blindness simulator.

About the color Neon Blue

Blue tubes need mercury

Neon gas by itself glows orange. Sign makers get blue by adding a little mercury to the tube, says the Wikipedia article on neon lighting. So a blue "neon" sign owes its color to a different element.

A bright cyan from a survey

Our #04D9FF is the neon blue from the xkcd color survey, where people named random colors on their screens in 2010. It is a bright cyan blue. Wikipedia lists neon blue three ways: #1B03A3, #4666FF and #4D4DFF. All three are deep purplish blues, far from ours.

Closer matches on this site are vivid sky blue and electric blue. Black text works well on #04D9FF, at 12.37 to 1.

Neon Blue in a user interface

A sample app screen with #04D9FF as the main color, on a light and a dark theme.

Light theme

Dark theme

Buttons and bars use #04D9FF as it is. On the light theme, #04D9FF is too hard to read as text (1.70:1), so links, the badge and outline text use #00829A there (4.51:1). Build a full color scheme around it in the UI color preview.

Color harmonies for Neon Blue

These schemes turn the hue of #04D9FF around the color wheel. Each swatch links to its own page.

Complementary

Two colors on opposite sides of the wheel. This gives the most contrast.

Open palette
this#04D9FF#FF2A04

Analogous

Hues that sit next to each other and look good together.

Open palette
#04FFA8this#04D9FF#045CFF

Triadic

Three hues spaced evenly around the wheel. Bold, but still balanced.

Open palette
this#04D9FF#FF04D9#D9FF04

Split complementary

A base color plus the two hues on each side of its opposite. Strong contrast that clashes less.

Open palette
this#04D9FF#FF045C#FFA804

Tetradic (rectangle)

Two pairs of opposite colors. Let one color lead and use the others less.

Open palette
this#04D9FF#2A04FF#FF2A04#D9FF04

Square

Four hues 90Β° apart, spread evenly around the wheel.

Open palette
this#04D9FF#A804FF#FF2A04#5CFF04

Monochromatic

One hue at different levels of lightness and saturation.

Open palette
#005766#009DB9#0DDAFF#60E7FF#B3F3FF

Gradients with Neon Blue

Four CSS gradients made from #04D9FF. Copy the code, or open one in the gradient generator to change it.

Soft tint

From a pale tint to the full color.

background: linear-gradient(90deg, #DFF8FF, #04D9FF);

Edit in the gradient generator

Deep shade

The color fading into a dark shade.

background: linear-gradient(180deg, #04D9FF, #003B48);

Edit in the gradient generator

Analogous

Its two neighbors on the color wheel.

background: linear-gradient(135deg, #04FFA8, #04D9FF, #045CFF);

Edit in the gradient generator

Triadic

A bold blend with a triadic color, through a clean middle.

background: linear-gradient(135deg, #04D9FF, #C496EC, #FF04D9);

Edit in the gradient generator

Shades, tints and tones of Neon Blue

Shades are darker, tints are lighter and tones are grayer. We make them in OKLCH so the steps look even. Hover a step to see its code, or click it to open it.

Design system scale (50 to 950)

Neon Blue sits at step 300. Export the full scale as CSS variables or Tailwind tokens from the picker.

  1. 50
    EAFAFF
  2. 100
    CFF4FF
  3. 200
    98E9FF
  4. 300
    04D9FF
  5. 400
    00B6D6
  6. 500
    0096B1
  7. 600
    00798F
  8. 700
    006072
  9. 800
    004B5A
  10. 900
    003742
  11. 950
    002129

Closest RAL, Tailwind and CSS colors

The nearest match to #04D9FF in three color systems that designers and builders use.

RAL ClassicRAL 6027 Light green#81C0BB, rough match (Ξ”E 10.6)Tailwind CSScyan-400 #22D3EE, very close (Ξ”E 2.5)CSS color nameslightskyblue #87CEFA, close (Ξ”E 6.5)

Ξ”E is the distance in OKLab: under 2 is hard to see, over 10 is a clearly different color. Browse all RAL colors, the Tailwind palette or the 148 CSS color names. RAL values on screens are only a guide, so check a real color chart before you order paint.

The named colors that look closest to this one (Ξ”E in OKLab). Browse all shades of cyan or search the color library.