#237DA1
Closest named color: Cerulean (#457B9D). oklch(55.5% 0.098 229.8), rgb(35, 125, 161).
Aa
White text reads best on this color (4.64:1).
About this color
#237DA1 is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 55%, its chroma 0.098 and its hue 230°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.024 away. White text reads best on it, at 4.64:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.51:1 |
| White text | 4.64:1 |
Values
| HEX | #237DA1 |
| RGB | rgb(35, 125, 161) |
| HSL | hsl(197, 64%, 38%) |
| OKLCH | oklch(55.5% 0.098 229.8) |
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 #237DA1 | 4.64:1 | AA | Lc -77.4 | Fine for body text |
| Black text on #237DA1 | 4.51:1 | AA | Lc 32.2 | Non-text elements, placeholder text |
| #237DA1 text on white | 4.64:1 | AA | Lc 71.9 | Content text, not long reading |
| #237DA1 text on black | 4.51:1 | AA | Lc -29.8 | 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
#E2ECF1
oklch(93.7% 0.013 228.9)
-
Step 200
200
#C9DDE6
oklch(88.5% 0.025 226.5)
-
Step 300
300
#A4C7D8
oklch(81% 0.044 228.9)
-
Step 400
400
#71A9C4
oklch(70.6% 0.071 229.8)
-
Step 500
500
#4894B6
oklch(63.2% 0.091 229.8)
-
Step 600
600 (this color)
#237DA1
oklch(55.5% 0.098 229.8)
-
Step 700
700
#146A8A
oklch(49.2% 0.091 229.3)
-
Step 800
800
#155670
oklch(42.6% 0.076 229.8)
-
Step 900
900
#1A475B
oklch(37.6% 0.059 230.5)
-
Step 950
950
#112A35
oklch(27.1% 0.037 229)
#237DA1 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) | #6A7BA3 | 0.068 |
| Deuteranopia (no green cones) | #5A6FA0 | 0.059 |
| Tritanopia (no blue cones) | #008789 | 0.057 |
| Achromatopsia (no color) | #747474 | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #237DA1
#237DA1
oklch(55.5% 0.098 229.8)
- #A1603B
#A1603B
oklch(55.4% 0.099 49.3)
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 #237DA1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.024
- Ocean #017B92 ΔE 0.028
- Nice Blue #107AB0 ΔE 0.028
- Dull Blue #49759C ΔE 0.033
- Sea Blue #047495 ΔE 0.034
- Teal Blue #01889F ΔE 0.034
- Stormy Blue #507B9C ΔE 0.035
- Muted Blue #3B719F ΔE 0.036
Use #237DA1 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.