#437FBC
Closest named color: Steel Blue (#4682B4). oklch(58.4% 0.113 250.7), rgb(67, 127, 188).
Aa
Black text reads best on this color (5.00:1).
About this color
#437FBC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.113 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.017 away. Black text reads best on it, at 5.00:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 5.00:1 |
| White text | 4.19:1 |
Values
| HEX | #437FBC |
| RGB | rgb(67, 127, 188) |
| HSL | hsl(210, 47%, 50%) |
| OKLCH | oklch(58.4% 0.113 250.7) |
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 #437FBC | 4.19:1 | AA large text | Lc -74.2 | Content text, not long reading |
| Black text on #437FBC | 5.00:1 | AA | Lc 35.3 | Non-text elements, placeholder text |
| #437FBC text on white | 4.19:1 | AA large text | Lc 68.7 | Content text, not long reading |
| #437FBC text on black | 5.00:1 | AA | Lc -32.9 | 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
#A9C4E1
oklch(81% 0.051 250.3)
-
Step 400
400
#7AA5D2
oklch(70.8% 0.081 250.1)
-
Step 500
500
#578DC6
oklch(63% 0.104 251)
-
Step 600
600 (this color)
#437FBC
oklch(58.4% 0.113 250.7)
-
Step 700
700
#2C639A
oklch(49% 0.106 250.9)
-
Step 800
800
#26517D
oklch(42.6% 0.088 251.1)
-
Step 900
900
#244464
oklch(37.8% 0.067 250)
-
Step 950
950
#16283B
oklch(27.1% 0.043 250.9)
#437FBC 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) | #6582BF | 0.039 |
| Deuteranopia (no green cones) | #5476BB | 0.028 |
| Tritanopia (no blue cones) | #008D95 | 0.089 |
| Achromatopsia (no color) | #7C7C7C | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #437FBC
#437FBC
oklch(58.4% 0.113 250.7)
- #A56E20
#A56E20
oklch(58.3% 0.113 70.6)
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 #437FBC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.017
- Cool Blue #4984B8 ΔE 0.018
- Windows Blue #3778BF ΔE 0.025
- Off Blue #5684AE ΔE 0.035
- Water Blue #0E87CC ΔE 0.036
- Nice Blue #107AB0 ΔE 0.041
- Dusty Blue #5A86AD ΔE 0.042
- Flat Blue #3C73A8 ΔE 0.043
Use #437FBC 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.