Color #E40303 Color / Colour Code #E40303
This page shows the hex color code for color #e40303 (#E40303). The colour is a red tone with 97% saturation and 45% lightness. Explore its conversions, colour palettes, gradients, accessibility data, and CSS code below.
Color Conversions
Accessibility Contrast
WCAG contrast ratios for #E40303 against common backgrounds.
Complementary Colors
#E40303 paired with its color wheel opposite for maximum contrast.
Analogous Colors
Hues at 330, 0, and 30 degrees for harmonious combinations.
Triadic Palette
Three colors at 0, 120, and 240 degrees.
Color Palettes Using #E40303
Five shades at lightness levels 15% through 85% while keeping hue at 0 and saturation at 97%. Use the darkest shade for text and the lightest for backgrounds to build a cohesive single-hue design system.
Adjacent hues from 0 to 45 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 0 with its complement at 180 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 #E40303
Lightness variations at hue 0 and 97% saturation.
CSS Gradients with #E40303
Design Use Cases for #E40303
High-Impact Accent
With 97% saturation, #E40303 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.
Primary Interface Color
At 45% lightness, #E40303 is in the mid-range, making it ideal for interactive elements like buttons, links, and selected states. This lightness level ensures good contrast against both light and dark adjacent elements in most layouts.
Urgency & Energy Signaling
#E40303 falls in the red spectrum (hue 0). 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 #E40303 (hue 0) to its complement at hue 180. For a subtler effect, try pairing with an analogous color at hue 30. Use CSS: background: linear-gradient(135deg, #e40303, #03e2e2);
CSS Code for #E40303
Similar Colors
Colors visually similar to #E40303 based on RGB, lightness, and hue variations.
Use This Color in Design Tools
Apply #E40303 across image editing and color design tools.
About Color #E40303 (#E40303)
#E40303 is a red color (colour) with RGB channel values of 228 red, 3 green, and 3 blue. The red channel is dominant by a ratio of 76.0:1 over the weakest channel. In HSL terms, the hue sits at 0 degrees with 97% saturation and 45% lightness, placing it in the warm range of the colour spectrum.
The perceived brightness of #E40303 is 70/255 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, 99% magenta, 99% yellow, and 11% key (black).
The WCAG contrast ratio of #E40303 against white is 4.87:1 and against black is 4.31:1. This meets the AA requirement (4.5:1) for normal text on white. For AAA compliance, consider darkening to at least 31% lightness.
The complementary colour #03E2E2 creates maximum visual tension when paired with #E40303. For more harmonious color combinations, use the analogous colours #E20373 and #E27303, 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 #E40303
- 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 #E40303?
- #E40303 is Color #E40303, a red color (colour) with RGB(228, 3, 3), HSL(0, 97%, 45%), and CMYK(0%, 99%, 99%, 11%). Its perceived brightness is 70/255.
- Is #E40303 accessible for text?
- Against white, #E40303 has a contrast ratio of 4.87:1 (passes AA for normal text). Against black, it has 4.31:1 (fails AA). Use the contrast checker tool for custom background pairings.
- What colours pair well with #E40303?
- The complementary colour is #03E2E2 (hue 180). For subtle color combinations, use analogous colours #E20373 and #E27303. The triadic palette adds #03E203 and #0303E2 for vibrant variety.
- How do I use #E40303 in CSS?
- Use any format: color: #e40303; or rgb(228, 3, 3); or hsl(0, 97%, 45%). For CSS custom properties: --color-primary: 0 97% 45%; 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.