#437DBB
Closest named color: Steel Blue (#4682B4). oklch(57.9% 0.114 251.8), rgb(67, 125, 187).
Aa
Black text reads best on this color (4.88:1).
About this color
#437DBB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.114 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.020 away. Black text reads best on it, at 4.88:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.114) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 4.88:1 |
| White text | 4.29:1 |
Values
| HEX | #437DBB |
| RGB | rgb(67, 125, 187) |
| HSL | hsl(211, 47%, 50%) |
| OKLCH | oklch(57.9% 0.114 251.8) |
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 #437DBB | 4.29:1 | AA large text | Lc -75.0 | Content text, not long reading |
| Black text on #437DBB | 4.88:1 | AA | Lc 34.6 | Non-text elements, placeholder text |
| #437DBB text on white | 4.29:1 | AA large text | Lc 69.5 | Content text, not long reading |
| #437DBB text on black | 4.88:1 | AA | Lc -32.2 | 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
#CCDBEC
oklch(88.5% 0.029 251.5)
-
Step 300
300
#A9C3E1
oklch(80.8% 0.051 252.1)
-
Step 400
400
#7BA4D3
oklch(70.7% 0.082 252.3)
-
Step 500
500
#588DC7
oklch(63.1% 0.105 251.8)
-
Step 600
600 (this color)
#437DBB
oklch(57.9% 0.114 251.8)
-
Step 700
700
#2E639B
oklch(49.1% 0.106 251.9)
-
Step 800
800
#27517D
oklch(42.7% 0.087 251.5)
-
Step 900
900
#254365
oklch(37.6% 0.069 252.8)
-
Step 950
950
#16283B
oklch(27.1% 0.043 250.9)
#437DBB 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) | #6280BE | 0.036 |
| Deuteranopia (no green cones) | #5275BA | 0.025 |
| Tritanopia (no blue cones) | #008B93 | 0.091 |
| Achromatopsia (no color) | #7A7A7A | 0.114 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #437DBB
#437DBB
oklch(57.9% 0.114 251.8)
- #A36D1C
#A36D1C
oklch(57.8% 0.114 71.6)
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 #437DBB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.020
- Windows Blue #3778BF ΔE 0.021
- Cool Blue #4984B8 ΔE 0.023
- Off Blue #5684AE ΔE 0.038
- Nice Blue #107AB0 ΔE 0.038
- Flat Blue #3C73A8 ΔE 0.039
- Water Blue #0E87CC ΔE 0.039
- Dusty Blue #5A86AD ΔE 0.045
Use #437DBB 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.