Color #210307 Color / Colour Code #210307
This page shows the hex color code for color #210307 (#210307). The colour is a red tone with 83% saturation and 7% lightness. Explore its conversions, colour palettes, gradients, accessibility data, and CSS code below.
Color Conversions
Accessibility Contrast
WCAG contrast ratios for #210307 against common backgrounds.
Complementary Colors
#210307 paired with its color wheel opposite for maximum contrast.
Analogous Colors
Hues at 322, 352, and 22 degrees for harmonious combinations.
Triadic Palette
Three colors at 352, 112, and 232 degrees.
Color Palettes Using #210307
Five shades at lightness levels 15% through 85% while keeping hue at 352 and saturation at 83%. Use the darkest shade for text and the lightest for backgrounds to build a cohesive single-hue design system.
Adjacent hues from 352 to 37 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 352 with its complement at 172 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 #210307
Lightness variations at hue 352 and 83% saturation.
CSS Gradients with #210307
Design Use Cases for #210307
Vibrant Brand Color
#210307 has a strong 83% saturation that makes it ideal for brand identity elements. Use it for logos, primary call-to-action buttons, hero section accents, and marketing materials where visual impact matters. This saturation level is eye-catching without being harsh.
Dark Mode Background
At just 7% lightness, #210307 works as a dark mode background or overlay color. Dark backgrounds reduce eye strain in low-light environments and make bright accent colors pop. Pair with light text (minimum 4.5:1 contrast ratio) for readability.
Urgency & Energy Signaling
#210307 falls in the red spectrum (hue 352). Red triggers urgency and excitement, making it effective for sale badges, countdown timers, error messages, and "limited time" labels. In data visualization, use it to flag negative values or critical thresholds.
Gradient Pairing
Create a gradient from #210307 (hue 352) to its complement at hue 172. For a subtler effect, try pairing with an analogous color at hue 22. Use CSS: background: linear-gradient(135deg, #210307, #03211d);
CSS Code for #210307
Similar Colors
Colors visually similar to #210307 based on RGB, lightness, and hue variations.
Use This Color in Design Tools
Apply #210307 across image editing and color design tools.
About Color #210307 (#210307)
#210307 is a red color (colour) with RGB channel values of 33 red, 3 green, and 7 blue. The red channel is dominant by a ratio of 11.0:1 over the weakest channel. In HSL terms, the hue sits at 352 degrees with 83% saturation and 7% lightness, placing it in the warm range of the colour spectrum.
The perceived brightness of #210307 is 12/255 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 0% cyan, 91% magenta, 79% yellow, and 87% key (black).
The WCAG contrast ratio of #210307 against white is 19.43:1 and against black is 1.08:1. This exceeds the AAA requirement (7:1) for normal text on white, making it excellent for body text and small UI labels on light backgrounds.
The complementary colour #03211D creates maximum visual tension when paired with #210307. For more harmonious color combinations, use the analogous colours #210316 and #210E03, 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 #210307
- 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 #210307?
- #210307 is Color #210307, a red color (colour) with RGB(33, 3, 7), HSL(352, 83%, 7%), and CMYK(0%, 91%, 79%, 87%). Its perceived brightness is 12/255.
- Is #210307 accessible for text?
- Against white, #210307 has a contrast ratio of 19.43:1 (passes AA for normal text). Against black, it has 1.08:1 (fails AA). Use the contrast checker tool for custom background pairings.
- What colours pair well with #210307?
- The complementary colour is #03211D (hue 172). For subtle color combinations, use analogous colours #210316 and #210E03. The triadic palette adds #072103 and #030721 for vibrant variety.
- How do I use #210307 in CSS?
- Use any format: color: #210307; or rgb(33, 3, 7); or hsl(352, 83%, 7%). For CSS custom properties: --color-primary: 352 83% 7%; 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.