#4377B3
Closest named color: Windows Blue (#3778BF). oklch(56.1% 0.109 253.3), rgb(67, 119, 179).
Aa
White text reads best on this color (4.63:1).
About this color
#4377B3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.109 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.020 away. White text reads best on it, at 4.63:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.52:1 |
| White text | 4.63:1 |
Values
| HEX | #4377B3 |
| RGB | rgb(67, 119, 179) |
| HSL | hsl(212, 46%, 48%) |
| OKLCH | oklch(56.1% 0.109 253.3) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #4377B3 | 4.63:1 | AA | Lc -77.5 | Fine for body text |
| Black text on #4377B3 | 4.52:1 | AA | Lc 32.1 | Non-text elements, placeholder text |
| #4377B3 text on white | 4.63:1 | AA | Lc 72.0 | Content text, not long reading |
| #4377B3 text on black | 4.52:1 | AA | Lc -29.7 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 600.
-
Step 50
50
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E3EBF3
oklch(93.6% 0.014 248)
-
Step 200
200
#CDDBEB
oklch(88.6% 0.027 251.7)
-
Step 300
300
#ABC3E0
oklch(80.9% 0.049 253.3)
-
Step 400
400
#7EA4D1
oklch(70.8% 0.078 253.1)
-
Step 500
500
#5C8CC5
oklch(63% 0.101 253.5)
-
Step 600
600 (this color)
#4377B3
oklch(56.1% 0.109 253.3)
-
Step 700
700
#336399
oklch(49.2% 0.102 252.9)
-
Step 800
800
#2B517C
oklch(42.8% 0.084 252.9)
-
Step 900
900
#274364
oklch(37.7% 0.066 253.5)
-
Step 950
950
#17273A
oklch(26.8% 0.042 253.5)
#4377B3 with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #5D7AB6 | 0.031 |
| Deuteranopia (no green cones) | #4E70B2 | 0.021 |
| Tritanopia (no blue cones) | #00858D | 0.089 |
| Achromatopsia (no color) | #757575 | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4377B3
#4377B3
oklch(56.1% 0.109 253.3)
- #9B691B
#9B691B
oklch(56.1% 0.109 72.9)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #4377B3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.020
- Flat Blue #3C73A8 ΔE 0.021
- Nice Blue #107AB0 ΔE 0.032
- Steel Blue #4682B4 ΔE 0.032
- French Blue #436BAD ΔE 0.034
- Muted Blue #3B719F ΔE 0.035
- Dull Blue #49759C ΔE 0.035
- Cool Blue #4984B8 ΔE 0.038
Use #4377B3 in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.