Color #21BBFD Color / Colour Code #21BBFD
This page shows the hex color code for color #21bbfd (#21BBFD). The colour is a blue tone with 98% saturation and 56% lightness. Explore its conversions, colour palettes, gradients, accessibility data, and CSS code below.
Color Conversions
Accessibility Contrast
WCAG contrast ratios for #21BBFD against common backgrounds.
Complementary Colors
#21BBFD paired with its color wheel opposite for maximum contrast.
Analogous Colors
Hues at 168, 198, and 228 degrees for harmonious combinations.
Triadic Palette
Three colors at 198, 318, and 78 degrees.
Color Palettes Using #21BBFD
Five shades at lightness levels 15% through 85% while keeping hue at 198 and saturation at 98%. Use the darkest shade for text and the lightest for backgrounds to build a cohesive single-hue design system.
Adjacent hues from 198 to 243 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 198 with its complement at 18 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 #21BBFD
Lightness variations at hue 198 and 98% saturation.
CSS Gradients with #21BBFD
Design Use Cases for #21BBFD
High-Impact Accent
With 98% saturation, #21BBFD 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.
Soft Accent & Highlight
With 56% lightness, #21BBFD has a softer, more approachable quality. It works well for hover states, subtle highlights, progress indicators, and secondary UI elements. This lightness range is particularly effective for tag backgrounds and status indicators.
Trust & Professional Identity
#21BBFD sits in the blue range (hue 198). Blue is the world's most popular color for corporate identities because it conveys trust, stability, and competence. Use it for navigation bars, link text, form focus states, and any element where user confidence matters. Financial, healthcare, and technology brands rely heavily on this hue range.
Gradient Pairing
Create a gradient from #21BBFD (hue 198) to its complement at hue 18. For a subtler effect, try pairing with an analogous color at hue 228. Use CSS: background: linear-gradient(135deg, #21bbfd, #fd6321);
CSS Code for #21BBFD
Similar Colors
Colors visually similar to #21BBFD based on RGB, lightness, and hue variations.
Use This Color in Design Tools
Apply #21BBFD across image editing and color design tools.
About Color #21BBFD (#21BBFD)
#21BBFD is a blue color (colour) with RGB channel values of 33 red, 187 green, and 253 blue. The blue channel is dominant by a ratio of 7.7:1 over the weakest channel. In HSL terms, the hue sits at 198 degrees with 98% saturation and 56% lightness, placing it in the cool range of the colour spectrum.
The perceived brightness of #21BBFD is 148/255 using the ITU-R BT.601 luma formula (0.299R + 0.587G + 0.114B). This is a medium-brightness color that can work with either dark or light text depending on font weight and size. For print production, the CMYK equivalent is 87% cyan, 26% magenta, 0% yellow, and 1% key (black).
The WCAG contrast ratio of #21BBFD against white is 2.19:1 and against black is 9.59:1. This does not meet AA requirements on white. Use it on dark backgrounds where it achieves 9.59:1, or use it exclusively for decorative purposes.
The complementary colour #FD6321 creates maximum visual tension when paired with #21BBFD. For more harmonious color combinations, use the analogous colours #21FDD1 and #214DFD, 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 #21BBFD
- 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 #21BBFD?
- #21BBFD is Color #21BBFD, a blue color (colour) with RGB(33, 187, 253), HSL(198, 98%, 56%), and CMYK(87%, 26%, 0%, 1%). Its perceived brightness is 148/255.
- Is #21BBFD accessible for text?
- Against white, #21BBFD has a contrast ratio of 2.19:1 (fails AA for normal text). Against black, it has 9.59:1 (passes AA). Use the contrast checker tool for custom background pairings.
- What colours pair well with #21BBFD?
- The complementary colour is #FD6321 (hue 18). For subtle color combinations, use analogous colours #21FDD1 and #214DFD. The triadic palette adds #FD21BB and #BBFD21 for vibrant variety.
- How do I use #21BBFD in CSS?
- Use any format: color: #21bbfd; or rgb(33, 187, 253); or hsl(198, 98%, 56%). For CSS custom properties: --color-primary: 198 98% 56%; 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.