#437BBD
Closest named color: Windows Blue (#3778BF). oklch(57.5% 0.118 253.8), rgb(67, 123, 189).
Aa
Black text reads best on this color (4.80:1).
About this color
#437BBD is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.118 and its hue 254°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.015 away. Black text reads best on it, at 4.80:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.118) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.80:1 |
| White text | 4.36:1 |
Values
| HEX | #437BBD |
| RGB | rgb(67, 123, 189) |
| HSL | hsl(212, 48%, 50%) |
| OKLCH | oklch(57.5% 0.118 253.8) |
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 #437BBD | 4.36:1 | AA large text | Lc -75.5 | Fine for body text |
| Black text on #437BBD | 4.80:1 | AA | Lc 34.0 | Non-text elements, placeholder text |
| #437BBD text on white | 4.36:1 | AA large text | Lc 70.0 | Content text, not long reading |
| #437BBD text on black | 4.80:1 | AA | Lc -31.6 | Non-text elements, placeholder text |
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
#E3EBF4
oklch(93.7% 0.015 251.2)
-
Step 200
200
#CCDBED
oklch(88.6% 0.03 253)
-
Step 300
300
#A9C3E3
oklch(80.8% 0.054 253.8)
-
Step 400
400
#7BA4D5
oklch(70.8% 0.085 253.3)
-
Step 500
500
#598CCA
oklch(63.1% 0.109 254.1)
-
Step 600
600 (this color)
#437BBD
oklch(57.5% 0.118 253.8)
-
Step 700
700
#2F629D
oklch(49.1% 0.11 253.7)
-
Step 800
800
#285080
oklch(42.7% 0.092 254.3)
-
Step 900
900
#254366
oklch(37.7% 0.07 253.4)
-
Step 950
950
#16273C
oklch(26.9% 0.046 254.4)
#437BBD 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) | #5E7FC0 | 0.033 |
| Deuteranopia (no green cones) | #4D74BC | 0.020 |
| Tritanopia (no blue cones) | #008A93 | 0.095 |
| Achromatopsia (no color) | #797979 | 0.118 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #437BBD
#437BBD
oklch(57.5% 0.118 253.8)
- #A26C0D
#A26C0D
oklch(57.4% 0.118 73.5)
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 #437BBD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.015
- Steel Blue #4682B4 ΔE 0.027
- Cool Blue #4984B8 ΔE 0.030
- Flat Blue #3C73A8 ΔE 0.038
- Nice Blue #107AB0 ΔE 0.039
- Water Blue #0E87CC ΔE 0.041
- Off Blue #5684AE ΔE 0.044
- French Blue #436BAD ΔE 0.047
Use #437BBD 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.