#437E9F
Closest named color: Cerulean (#457B9D). oklch(56.7% 0.08 235.1), rgb(67, 126, 159).
Aa
Black text reads best on this color (4.72:1).
About this color
#437E9F is a medium-dark, moderately saturated blue. In OKLCH its lightness is 57%, its chroma 0.080 and its hue 235°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.008 away. Black text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | moderately saturated (0.080) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.72:1 |
| White text | 4.44:1 |
Values
| HEX | #437E9F |
| RGB | rgb(67, 126, 159) |
| HSL | hsl(202, 41%, 44%) |
| OKLCH | oklch(56.7% 0.08 235.1) |
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 #437E9F | 4.44:1 | AA large text | Lc -76.2 | Fine for body text |
| Black text on #437E9F | 4.72:1 | AA | Lc 33.4 | Non-text elements, placeholder text |
| #437E9F text on white | 4.44:1 | AA large text | Lc 70.7 | Content text, not long reading |
| #437E9F text on black | 4.72:1 | AA | Lc -31.0 | 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
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E4EBF0
oklch(93.6% 0.01 238.5)
-
Step 200
200
#CDDCE5
oklch(88.6% 0.02 233.9)
-
Step 300
300
#ABC5D5
oklch(80.9% 0.036 234.9)
-
Step 400
400
#7EA7C0
oklch(70.7% 0.058 235.4)
-
Step 500
500
#5B91B0
oklch(63.1% 0.074 234.8)
-
Step 600
600 (this color)
#437E9F
oklch(56.7% 0.08 235.1)
-
Step 700
700
#316785
oklch(49% 0.075 235.4)
-
Step 800
800
#2A546C
oklch(42.6% 0.062 235.8)
-
Step 900
900
#274658
oklch(37.8% 0.048 235.5)
-
Step 950
950
#172933
oklch(27% 0.03 233.8)
#437E9F 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) | #6E7DA1 | 0.050 |
| Deuteranopia (no green cones) | #62739E | 0.044 |
| Tritanopia (no blue cones) | #008789 | 0.060 |
| Achromatopsia (no color) | #787878 | 0.080 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #437E9F
#437E9F
oklch(56.7% 0.08 235.1)
- #9B6A47
#9B6A47
oklch(56.8% 0.08 55.9)
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 #437E9F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.008
- Stormy Blue #507B9C ΔE 0.014
- Dull Blue #49759C ΔE 0.026
- Steel Blue #4682B4 ΔE 0.033
- Off Blue #5684AE ΔE 0.035
- Metallic Blue #4F738E ΔE 0.036
- Teal Blue #01889F ΔE 0.039
- Flat Blue #3C73A8 ΔE 0.040
Use #437E9F 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.