Color #21800A Color / Colour Code #21800A
This page shows the hex color code for color #21800a (#21800A). The colour is a green tone with 86% saturation and 27% lightness. Explore its conversions, colour palettes, gradients, accessibility data, and CSS code below.
Color Conversions
Accessibility Contrast
WCAG contrast ratios for #21800A against common backgrounds.
Complementary Colors
#21800A paired with its color wheel opposite for maximum contrast.
Analogous Colors
Hues at 78, 108, and 138 degrees for harmonious combinations.
Triadic Palette
Three colors at 108, 228, and 348 degrees.
Color Palettes Using #21800A
Five shades at lightness levels 15% through 85% while keeping hue at 108 and saturation at 86%. Use the darkest shade for text and the lightest for backgrounds to build a cohesive single-hue design system.
Adjacent hues from 108 to 153 degrees create a warm, unified palette. This analogous scheme works for marketing materials, seasonal campaigns, and any design that needs visual warmth without clashing colors.
Combines the base color at hue 108 with its complement at 288 and two adjacent cool tones. This split-complementary approach provides strong visual contrast while remaining more balanced than a pure complementary scheme.
Five evenly spaced hues at 40% saturation and 80% lightness. Pastels are gentle on the eyes and work well for dashboards, onboarding screens, category tags, and any interface where multiple distinct colors are needed without visual aggression.
Shades & Tints of #21800A
Lightness variations at hue 108 and 86% saturation.
CSS Gradients with #21800A
Design Use Cases for #21800A
High-Impact Accent
With 86% saturation, #21800A is highly vivid. Reserve this for elements that need maximum attention: primary action buttons, notification badges, error states, or promotional banners. Use sparingly alongside neutral tones to avoid visual fatigue.
Deep Accent & Text Color
#21800A at 27% lightness is dark enough for readable body text on light backgrounds while retaining its green character. Use for headings, emphasized text, or deep accent borders. It provides contrast without the harshness of pure black.
Success & Growth Indicators
#21800A falls in the green range (hue 108). Green universally represents success, growth, and safety. Use it for confirmation messages, positive chart data, eco-friendly badges, and health metrics. In financial dashboards, green indicates gains and positive performance.
Gradient Pairing
Create a gradient from #21800A (hue 108) to its complement at hue 288. For a subtler effect, try pairing with an analogous color at hue 138. Use CSS: background: linear-gradient(135deg, #21800a, #680a80);
CSS Code for #21800A
Similar Colors
Colors visually similar to #21800A based on RGB, lightness, and hue variations.
Use This Color in Design Tools
Apply #21800A across image editing and color design tools.
About Color #21800A (#21800A)
#21800A is a green color (colour) with RGB channel values of 33 red, 128 green, and 10 blue. The green channel is dominant by a ratio of 12.8:1 over the weakest channel. In HSL terms, the hue sits at 108 degrees with 86% saturation and 27% lightness, placing it in the neutral-to-cool range of the colour spectrum.
The perceived brightness of #21800A is 86/255 using the ITU-R BT.601 luma formula (0.299R + 0.587G + 0.114B). This appears dark to the human eye, so pair it with light text for adequate readability. For print production, the CMYK equivalent is 74% cyan, 0% magenta, 92% yellow, and 50% key (black).
The WCAG contrast ratio of #21800A against white is 5.05:1 and against black is 4.16:1. This meets the AA requirement (4.5:1) for normal text on white. For AAA compliance, consider darkening to at least 19% lightness.
The complementary colour #680A80 creates maximum visual tension when paired with #21800A. For more harmonious color combinations, use the analogous colours #5D800A and #0A802D, which sit 30 degrees on either side of the hue wheel. To build a complete design system, start with the monochromatic scale above for consistent shade variations, then add one complementary or triadic accent for interactive elements.
How to Explore Color #21800A
- Enter your color value in HEX format.
- The tool converts it to RGB, HSL, CMYK format in real time.
- Copy the converted value to your clipboard.
What is HEX to RGB, HSL, CMYK color conversion
Converting from HEX to RGB, HSL, CMYK translates a color value between two different color models. Different color models are used in web design (HEX, RGB), print (CMYK), and color theory (HSL, HSV).
Related Tools & Colors
Frequently Asked Questions
- What color / colour is #21800A?
- #21800A is Color #21800A, a green color (colour) with RGB(33, 128, 10), HSL(108, 86%, 27%), and CMYK(74%, 0%, 92%, 50%). Its perceived brightness is 86/255.
- Is #21800A accessible for text?
- Against white, #21800A has a contrast ratio of 5.05:1 (passes AA for normal text). Against black, it has 4.16:1 (fails AA). Use the contrast checker tool for custom background pairings.
- What colours pair well with #21800A?
- The complementary colour is #680A80 (hue 288). For subtle color combinations, use analogous colours #5D800A and #0A802D. The triadic palette adds #0A2180 and #800A21 for vibrant variety.
- How do I use #21800A in CSS?
- Use any format: color: #21800a; or rgb(33, 128, 10); or hsl(108, 86%, 27%). For CSS custom properties: --color-primary: 108 86% 27%; then use it as hsl(var(--color-primary)).
- Is this color / colour explorer free?
- Yes, completely free with no signup required. All colour calculations run in your browser. You can explore any valid hex color code, not just the pre-generated palette.