#37D9EF
Closest named color: Aqua Blue (#02D8E9). oklch(81.5% 0.13 208.8), rgb(55, 217, 239).
Aa
Black text reads best on this color (12.33:1).
About this color
#37D9EF is a light, moderately saturated teal or cyan. In OKLCH its lightness is 81%, its chroma 0.130 and its hue 209°. Its hue sits on the cool side of the wheel. The nearest named color is Aqua Blue (#02D8E9), ΔE 0.015 away. Black text reads best on it, at 12.33:1.
| Hue family | Teals and cyans |
| Lightness | light (81%) |
| Chroma | moderately saturated (0.130) |
| Temperature | cool |
| Nearest name | Aqua Blue (#02D8E9) |
| Black text | 12.33:1 |
| White text | 1.70:1 |
Values
| HEX | #37D9EF |
| RGB | rgb(55, 217, 239) |
| HSL | hsl(187, 85%, 58%) |
| OKLCH | oklch(81.5% 0.13 208.8) |
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 #37D9EF | 1.70:1 | Fails | Lc -33.8 | Non-text elements, placeholder text |
| Black text on #37D9EF | 12.33:1 | AAA | Lc 73.8 | Content text, not long reading |
| #37D9EF text on white | 1.70:1 | Fails | Lc 30.0 | Dividers and decoration only |
| #37D9EF text on black | 12.33:1 | AAA | Lc -72.8 | Content text, not long reading |
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 300.
-
Step 50
50
#E9F9FC
oklch(97.1% 0.017 210.2)
-
Step 100
100
#CEF1F7
oklch(93.5% 0.037 209.1)
-
Step 200
200
#A0E7F3
oklch(88.5% 0.072 209.1)
-
Step 300
300 (this color)
#37D9EF
oklch(81.5% 0.13 208.8)
-
Step 400
400
#00B5C9
oklch(70.8% 0.122 208.7)
-
Step 500
500
#009BAC
oklch(63.1% 0.109 208.4)
-
Step 600
600
#008291
oklch(55.5% 0.096 208.9)
-
Step 700
700
#006D7A
oklch(49% 0.084 209.1)
-
Step 800
800
#005A64
oklch(42.8% 0.073 207.9)
-
Step 900
900
#004B54
oklch(37.8% 0.065 208.5)
-
Step 950
950
#002C33
oklch(26.9% 0.047 211.1)
#37D9EF 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) | #C5D1F0 | 0.123 |
| Deuteranopia (no green cones) | #ACBFEF | 0.112 |
| Tritanopia (no blue cones) | #00E3E0 | 0.041 |
| Achromatopsia (no color) | #C6C6C6 | 0.130 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37D9EF
#37D9EF
oklch(81.5% 0.13 208.8)
- #FFA89C
#FFA89C
oklch(81.4% 0.105 28.2)
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 #37D9EF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Aqua Blue #02D8E9 ΔE 0.015
- Vivid Sky Blue #4CC9F0 ΔE 0.045
- Medium Turquoise #48D1CC ΔE 0.048
- Bright Sky Blue #02CCFE ΔE 0.050
- Dark Turquoise #00CED1 ΔE 0.051
- Turquoise #40E0D0 ΔE 0.054
- Sky Blue #87CEEB ΔE 0.057
- Lightblue #7BC8F6 ΔE 0.063
Use #37D9EF 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.