#437FBF
Closest named color: Cool Blue (#4984B8). oklch(58.6% 0.117 251.8), rgb(67, 127, 191).
Aa
Black text reads best on this color (5.02:1).
About this color
#437FBF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.117 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.021 away. Black text reads best on it, at 5.02:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.117) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.02:1 |
| White text | 4.17:1 |
Values
| HEX | #437FBF |
| RGB | rgb(67, 127, 191) |
| HSL | hsl(211, 49%, 51%) |
| OKLCH | oklch(58.6% 0.117 251.8) |
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 #437FBF | 4.17:1 | AA large text | Lc -74.1 | Content text, not long reading |
| Black text on #437FBF | 5.02:1 | AA | Lc 35.5 | Non-text elements, placeholder text |
| #437FBF text on white | 4.17:1 | AA large text | Lc 68.6 | Content text, not long reading |
| #437FBF text on black | 5.02:1 | AA | Lc -33.1 | 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
#A8C4E2
oklch(81% 0.052 250.3)
-
Step 400
400
#7AA4D4
oklch(70.7% 0.084 252.3)
-
Step 500
500
#568DC9
oklch(63.1% 0.108 251.8)
-
Step 600
600 (this color)
#437FBF
oklch(58.6% 0.117 251.8)
-
Step 700
700
#2C639C
oklch(49.1% 0.109 251.7)
-
Step 800
800
#26517F
oklch(42.8% 0.09 252.1)
-
Step 900
900
#244366
oklch(37.7% 0.071 252.7)
-
Step 950
950
#15283C
oklch(27.1% 0.045 250.9)
#437FBF 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) | #6382C2 | 0.036 |
| Deuteranopia (no green cones) | #5277BE | 0.024 |
| Tritanopia (no blue cones) | #008E96 | 0.093 |
| Achromatopsia (no color) | #7C7C7C | 0.117 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #437FBF
#437FBF
oklch(58.6% 0.117 251.8)
- #A66F19
#A66F19
oklch(58.6% 0.117 72.2)
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 #437FBF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.021
- Steel Blue #4682B4 ΔE 0.021
- Windows Blue #3778BF ΔE 0.024
- Water Blue #0E87CC ΔE 0.034
- Off Blue #5684AE ΔE 0.038
- Nice Blue #107AB0 ΔE 0.043
- Dusty Blue #5A86AD ΔE 0.045
- Flat Blue #3C73A8 ΔE 0.046
Use #437FBF 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.