Color #303B88 Color / Colour Code #303B88
This page shows the hex color code for color #303b88 (#303B88). The colour is a blue tone with 48% saturation and 36% lightness. Explore its conversions, colour palettes, gradients, accessibility data, and CSS code below.
Color Conversions
Accessibility Contrast
WCAG contrast ratios for #303B88 against common backgrounds.
Complementary Colors
#303B88 paired with its color wheel opposite for maximum contrast.
Analogous Colors
Hues at 203, 233, and 263 degrees for harmonious combinations.
Triadic Palette
Three colors at 233, 353, and 113 degrees.
Color Palettes Using #303B88
Five shades at lightness levels 15% through 85% while keeping hue at 233 and saturation at 48%. Use the darkest shade for text and the lightest for backgrounds to build a cohesive single-hue design system.
Adjacent hues from 233 to 278 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 233 with its complement at 53 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 #303B88
Lightness variations at hue 233 and 48% saturation.
CSS Gradients with #303B88
Design Use Cases for #303B88
Balanced UI Color
At 48% saturation, #303B88 strikes a balance between vibrancy and restraint. This makes it versatile for primary UI elements like navigation bars, card headers, and form accents. It draws attention without overwhelming adjacent content.
Primary Interface Color
At 36% lightness, #303B88 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.
Trust & Professional Identity
#303B88 sits in the blue range (hue 233). 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 #303B88 (hue 233) to its complement at hue 53. For a subtler effect, try pairing with an analogous color at hue 263. Use CSS: background: linear-gradient(135deg, #303b88, #887e30);
CSS Code for #303B88
Similar Colors
Colors visually similar to #303B88 based on RGB, lightness, and hue variations.
Use This Color in Design Tools
Apply #303B88 across image editing and color design tools.
About Color #303B88 (#303B88)
#303B88 is a blue color (colour) with RGB channel values of 48 red, 59 green, and 136 blue. The blue channel is dominant by a ratio of 2.8:1 over the weakest channel. In HSL terms, the hue sits at 233 degrees with 48% saturation and 36% lightness, placing it in the cool range of the colour spectrum.
The perceived brightness of #303B88 is 64/255 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 65% cyan, 57% magenta, 0% yellow, and 47% key (black).
The WCAG contrast ratio of #303B88 against white is 9.97:1 and against black is 2.11:1. 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 #887E30 creates maximum visual tension when paired with #303B88. For more harmonious color combinations, use the analogous colours #306688 and #523088, 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 #303B88
- 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 #303B88?
- #303B88 is Color #303B88, a blue color (colour) with RGB(48, 59, 136), HSL(233, 48%, 36%), and CMYK(65%, 57%, 0%, 47%). Its perceived brightness is 64/255.
- Is #303B88 accessible for text?
- Against white, #303B88 has a contrast ratio of 9.97:1 (passes AA for normal text). Against black, it has 2.11:1 (fails AA). Use the contrast checker tool for custom background pairings.
- What colours pair well with #303B88?
- The complementary colour is #887E30 (hue 53). For subtle color combinations, use analogous colours #306688 and #523088. The triadic palette adds #88303A and #3A8830 for vibrant variety.
- How do I use #303B88 in CSS?
- Use any format: color: #303b88; or rgb(48, 59, 136); or hsl(233, 48%, 36%). For CSS custom properties: --color-primary: 233 48% 36%; 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.