#237399
Closest named color: Sea Blue (#047495). oklch(52.6% 0.096 233.8), rgb(35, 115, 153).
Aa
White text reads best on this color (5.27:1).
About this color
#237399 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 53%, its chroma 0.096 and its hue 234°. Its hue sits on the cool side of the wheel. The nearest named color is Sea Blue (#047495), ΔE 0.014 away. White text reads best on it, at 5.27:1.
| Hue family | Blues |
| Lightness | medium-dark (53%) |
| Chroma | moderately saturated (0.096) |
| Temperature | cool |
| Nearest name | Sea Blue (#047495) |
| Black text | 3.98:1 |
| White text | 5.27:1 |
Values
| HEX | #237399 |
| RGB | rgb(35, 115, 153) |
| HSL | hsl(199, 63%, 37%) |
| OKLCH | oklch(52.6% 0.096 233.8) |
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 #237399 | 5.27:1 | AA | Lc -81.2 | Fine for body text |
| Black text on #237399 | 3.98:1 | AA large text | Lc 28.2 | Dividers and decoration only |
| #237399 text on white | 5.27:1 | AA | Lc 75.9 | Fine for body text |
| #237399 text on black | 3.98:1 | AA large text | Lc -25.9 | Dividers and decoration only |
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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E2EBF1
oklch(93.5% 0.013 236.6)
-
Step 200
200
#CBDCE7
oklch(88.5% 0.024 236)
-
Step 300
300
#A6C6D8
oklch(80.9% 0.043 232.7)
-
Step 400
400
#75A8C5
oklch(70.6% 0.069 234)
-
Step 500
500
#4E92B7
oklch(63% 0.089 234.4)
-
Step 600
600 (this color)
#237399
oklch(52.6% 0.096 233.8)
-
Step 700
700
#20688B
oklch(49% 0.089 234.3)
-
Step 800
800
#1D5571
oklch(42.6% 0.074 234.2)
-
Step 900
900
#1E465B
oklch(37.5% 0.057 234.1)
-
Step 950
950
#132935
oklch(26.9% 0.036 234.1)
#237399 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) | #60729B | 0.060 |
| Deuteranopia (no green cones) | #506798 | 0.050 |
| Tritanopia (no blue cones) | #007D80 | 0.059 |
| Achromatopsia (no color) | #6C6C6C | 0.096 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #237399
#237399
oklch(52.6% 0.096 233.8)
- #955A31
#955A31
oklch(52.6% 0.096 53.8)
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 #237399, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sea Blue #047495 ΔE 0.014
- Ocean Blue #03719C ΔE 0.015
- Muted Blue #3B719F ΔE 0.022
- Ocean #017B92 ΔE 0.030
- Flat Blue #3C73A8 ΔE 0.032
- Dull Blue #49759C ΔE 0.034
- Nice Blue #107AB0 ΔE 0.037
- Cerulean #457B9D ΔE 0.039
Use #237399 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.