Green 5
green-5 · #51CF66
HEX
#51CF66
RGB
rgb(81, 207, 102)
CMYK
cmyk(61%, 0%, 51%, 19%)
HSL
hsl(130, 57%, 56%)
LAB
lab(74.4, -56.6, 41.8)
What is Green 5?
Green 5 is the green-5 reference in the Open Color. Its sRGB value is #51CF66 (rgb 81, 207, 102). It sits in the green family. Open Color, an open-source color palette by Heeyeun designed for UI work. 13 hues across 10 shades (0 to 9) tuned for screen legibility and accessibility. See disclaimer for accuracy and trademark notes.
Accessibility
WCAG 2.1 contrast checks for Green 5 as a background.
Black text on this color
White text on this color
Shades, tints & tonal scale of Green 5
An 11-step tonal scale derived from Green 5 (#51CF66). Click any swatch to copy its HEX. Use these as a starting point for design tokens, hover states, and disabled states in a design system.
50
#F1FBF3
#F1FBF3
100
#E3F7E7
#E3F7E7
200
#C7F0CE
#C7F0CE
300
#A8E7B3
#A8E7B3
400
#7DDB8C
#7DDB8C
500
#51CF66
#51CF66
600
#45B057
#45B057
700
#358742
#358742
800
#245D2E
#245D2E
900
#14341A
#14341A
950
#0A190C
#0A190C
Lighter tints (mixed with white)
15%
#81D78C
30%
#A1DFA8
45%
#BBE6BF
60%
#D0EDD3
75%
#E3F4E5
Darker shades (mixed with black)
15%
#4BC15E
30%
#44B056
45%
#3C9E4C
60%
#338941
75%
#276E33
Color harmonies for Green 5
Classic color-theory harmonies derived from rotating the hue of Green 5. Use these to build accent palettes, brand systems, and accessible UI color pairings.
Complementary
180° opposite — strongest contrast
#51CF66
#51CF66
#CF4FB9
#CF4FB9
Triadic
Three colors 120° apart
#51CF66
#51CF66
#644FCF
#644FCF
#CF644F
#CF644F
Analogous
Two neighbors ±30° on the wheel
#79CF4F
#79CF4F
#51CF66
#51CF66
#4FCFA4
#4FCFA4
Split-complementary
Base + two colors flanking its complement
#51CF66
#51CF66
#A44FCF
#A44FCF
#CF4F79
#CF4F79
Tetradic
Two complementary pairs
#51CF66
#51CF66
#4FB9CF
#4FB9CF
#CF4FB9
#CF4FB9
#CF644F
#CF644F
Square
Four colors evenly spaced 90° apart
#51CF66
#51CF66
#4F79CF
#4F79CF
#CF4FB9
#CF4FB9
#CFA44F
#CFA44F
Green 5 in every color space
Full conversion of Green 5 across the color spaces designers and developers actually use — including OKLCH (the perceptually-uniform space that powers Tailwind v4 and CSS Color Module Level 4) and HWB.
HEX
#51CF66
RGB
rgb(81, 207, 102)
CMYK
cmyk(61%, 0%, 51%, 19%)
HSL
hsl(130, 57%, 56%)
HSV
hsv(130, 61%, 81%)
HWB
hwb(130 32% 19%)
CIE Lab
lab(74.4 -56.6 41.8)
OKLCH
oklch(76.0% 0.183 146.6)
XYZ (D65)
xyz(28.10, 47.33, 20.22)
Copy-ready code for Green 5
Drop-in snippets for CSS, Tailwind, Sass, iOS Swift, and Android XML. Click the copy button on any snippet to put it on your clipboard.
CSS
color: #51CF66;
background-color: #51CF66;CSS variable
:root {
--color-green-5: #51CF66;
}Tailwind config
// tailwind.config.js
colors: {
'green-5': '#51CF66',
}Sass
$color-green-5: #51CF66;Swift UIColor
UIColor(red: 0.318, green: 0.812, blue: 0.400, alpha: 1.0)Android XML
<color name="green-5">#51CF66</color>Closest match in every color system
The nearest Green 5 equivalent in every other color system on this site, ranked by ΔE2000 perceptual distance. Useful when translating between design-system, web-standard, and industrial color references.
Closest in Open Color
Top 6 ΔE2000-closest entries within the same collection.
Closest Pantone matches
Top 6 ΔE2000-closest Pantone references. Cross-system matching is approximate — see disclaimer.
Closest RAL Classic matches
Top 6 ΔE2000-closest RAL Classic references for industrial coating cross-reference.
RAL 6018
#57A639
Yellow green
RAL 6021
#89AC76
Pale green
RAL 6019
#BDECB6
Pastel green
RAL 6017
#4C9141
May green
RAL 1000
#BEBD7F
Green beige
RAL 1020
#999950
Olive yellow
FAQ about Green 5
What is the HEX code for Green 5?
Green 5 (green-5) has the HEX code #51CF66. In RGB it is rgb(81, 207, 102), and in CMYK it is cmyk(61%, 0%, 51%, 19%).
What is the OKLCH value of Green 5?
Green 5 converts to oklch(0.760 0.183 146.6). OKLCH is the perceptually uniform color space used by Tailwind v4 and CSS Color Module Level 4.
Is Green 5 accessible for body text?
Used as a background, Green 5 has a contrast ratio of 10.47:1 with black text and 2.01:1 with white text. WCAG 2.1 AA requires 4.5:1 for normal text. The current recommendation is to use black text and verify in real UI context.
What is the closest Pantone to Green 5?
The closest Pantone reference to Green 5 by ΔE2000 perceptual distance is Pantone 354 C (#00B140). Cross-system Pantone matching is approximate; for color-critical print work, verify with a physical Pantone guide.
What is the closest RAL color to Green 5?
The closest RAL Classic reference to Green 5 by ΔE2000 distance is RAL 6018 (Yellow green, #57A639). RAL is a German industrial coating standard commonly used for paint, powder coat, and architectural specification.
What is the complementary color of Green 5?
The complementary color (180° opposite on the HSL color wheel) of Green 5 is #CF4FB9. Use it for high-contrast accents, error states, or call-to-action pairings.
Data provenance & source
Open Color (Yeun)
Open Color, an open-source color palette by Heeyeun designed for UI designers and developers. 13 hues across 10 shades. Use as a designer-friendly palette alternative to Tailwind. Values are intentionally chosen for UI legibility and accessibility.
- Source type
- derived
- Confidence
- high
- License
- MIT
- Last reviewed
- 2026-05-24
Workflow tags
Open Color values are tuned for digital UI. For print, treat as a starting point and proof against the substrate.