#4040BF Color
#4040BF is rgb(64, 64, 191) in RGB, hsl(240, 50%, 50%) in HSL, and about cmyk(66%, 66%, 0%, 25%) in CMYK. It has no registered color name of its own — the closest is Persian Blue (#1C39BB), clearly related but distinguishable side by side at ΔE 6.1. White text is the more readable choice on this background.
#4040BFrgb(64, 64, 191)hsl(240, 50%, 50%)hsv(240, 66%, 75%)cmyk(66%, 66%, 0%, 25%)oklch(45.7% 0.193 275.6)lab(33.93% 32.07 -68.06)lch(33.93% 75.23 295.23)What #4040BF Is Called
Most hex codes have no name: there are 16.7 million of them and a few thousand registered names. These are the named colors nearest to #4040BF, ordered by CIE76 distance in CIELAB. Anything under about ΔE 2 is a difference most people cannot see.
Browse the full index of named colors A-Z or every blue in the library.
#4040BF Channel Values
How #4040BF breaks down in each color model. Hue is measured in degrees around the color wheel; saturation, lightness, and the CMYK inks are percentages.
| Model | Channels | Notes |
|---|---|---|
| RGB | R 64 · G 64 · B 191 | 8-bit channels as sent to the display |
| HSL | H 240° · S 50% · L 50% | Easiest model for building lighter and darker variants |
| HSV | H 240° · S 66% · V 75% | Matches the picker in most design tools |
| CMYK | C 66% · M 66% · Y 0% · K 25% | Approximate ink mix; confirm with an ICC profile before printing |
| Luminance | 7.77:1 vs white · 2.7:1 vs black | WCAG 2.2 relative-luminance contrast ratios |
Text Contrast & Accessibility
WCAG 2.2 contrast ratios for text on a #4040BF background. AA requires 4.5:1 for normal text and 3:1 for large text; AAA requires 7:1. Contrast is one check, not a full accessibility review.
Need a specific ratio against another background? Open #4040BF in the contrast checker.
Colors That Go With #4040BF
Pairings derived from color-wheel relationships. The complementary color sits opposite #4040BF; analogous colors sit beside it; triadic and split-complementary sets spread evenly around the wheel. Select any swatch for its own breakdown.
Tints & Shades of #4040BF
Lighter tints and darker shades built by moving the lightness channel while holding hue and saturation, which is what you want for hover states, backgrounds, and text variants.
Want a full 50-950 ramp with semantic roles? Generate design tokens from #4040BF.
How #4040BF Looks with Color Vision Deficiency
Simulated with the Viénot, Brettel & Mollon LMS projection model. Anomalous types are rendered as partial versions of the matching dichromacy, which is an approximation rather than a per-person clinical model.
#4040BF#4040BF#4040BF#4040BF#4040BF#005D5D#21538F#525252Using #4040BF in Code
Copy-ready declarations for the places this color usually ends up.
--color-4040bf: #4040BF;background-color: #4040BF;colors: { 'color-4040bf': '#4040BF' }Color(red: 0.251, green: 0.251, blue: 0.749)<color name="color_4040bf">#4040BF</color>fill="#4040BF"More Blue Colors
#4040BF sits in the blue family. These are its neighbours across that family's full range, each with its own breakdown.
#4040BF Frequently Asked Questions
What color is #4040BF?
#4040BF is a mid-tone blue — rgb(64, 64, 191) in RGB and hsl(240, 50%, 50%) in HSL. It carries no registered color name of its own; the closest named color is Persian Blue (#1C39BB), which is clearly related but distinguishable side by side at a CIE76 distance of 6.1.
What is the RGB value of #4040BF?
#4040BF is rgb(64, 64, 191) — red 64, green 64, and blue 191 on the 0-255 scale.
What is the CMYK value of #4040BF?
#4040BF converts to approximately cmyk(66%, 66%, 0%, 25%). CMYK output is a mathematical approximation for planning; confirm production print colors with your printer and ICC profile.
Should text on #4040BF be black or white?
White text is the more readable choice. #4040BF scores 7.77:1 against white and 2.7:1 against black, and WCAG 2.2 asks for at least 4.5:1 for normal body text.
Can I write #4040BF as a CSS color keyword?
No. #4040BF is not one of the CSS color keywords, so it has to be written as a hex, rgb() or hsl() value. The closest keyword is slateblue (#6A5ACD) at a CIE76 distance of 14.36, which is visibly different.
Open #4040BF in a Tool
Keep exploring: every blue in the color library, the guide to shades of blue, or the full color library.