#37B8EE
Closest named color: Deep Sky Blue (#00BFFF). oklch(73.7% 0.133 231), rgb(55, 184, 238).
Aa
Black text reads best on this color (9.25:1).
About this color
#37B8EE is a medium-light, moderately saturated blue. In OKLCH its lightness is 74%, its chroma 0.133 and its hue 231°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.027 away. Black text reads best on it, at 9.25:1.
| Hue family | Blues |
| Lightness | medium-light (74%) |
| Chroma | moderately saturated (0.133) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 9.25:1 |
| White text | 2.26:1 |
Values
| HEX | #37B8EE |
| RGB | rgb(55, 184, 238) |
| HSL | hsl(198, 84%, 57%) |
| OKLCH | oklch(73.7% 0.133 231) |
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 #37B8EE | 2.26:1 | Fails | Lc -49.1 | Large or bold text, headings |
| Black text on #37B8EE | 9.25:1 | AAA | Lc 59.6 | Large or bold text, headings |
| #37B8EE text on white | 2.26:1 | Fails | Lc 44.3 | Non-text elements, placeholder text |
| #37B8EE text on black | 9.25:1 | AAA | Lc -57.8 | Large or bold text, headings |
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 400.
-
Step 50
50
#EEF7FC
oklch(97.1% 0.012 231.7)
-
Step 100
100
#DBEDF7
oklch(93.6% 0.023 231.8)
-
Step 200
200
#BBDFF2
oklch(88.4% 0.046 231)
-
Step 300
300
#88CBED
oklch(81% 0.083 231.2)
-
Step 400
400 (this color)
#37B8EE
oklch(73.7% 0.133 231)
-
Step 500
500
#0096C8
oklch(63.1% 0.127 231)
-
Step 600
600
#007EA9
oklch(55.6% 0.112 231.2)
-
Step 700
700
#006A8E
oklch(49.1% 0.099 230.6)
-
Step 800
800
#005775
oklch(42.8% 0.086 230.3)
-
Step 900
900
#004862
oklch(37.7% 0.076 230.8)
-
Step 950
950
#002B3C
oklch(27.1% 0.054 230.4)
#37B8EE 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) | #9DB6F1 | 0.090 |
| Deuteranopia (no green cones) | #84A4ED | 0.077 |
| Tritanopia (no blue cones) | #00C7CA | 0.079 |
| Achromatopsia (no color) | #ACACAC | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37B8EE
#37B8EE
oklch(73.7% 0.133 231)
- #EC9057
#EC9057
oklch(73.8% 0.133 51.2)
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 #37B8EE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.027
- Vivid Sky Blue #4CC9F0 ΔE 0.050
- Bright Sky Blue #02CCFE ΔE 0.053
- Turquoise Blue #06B1C4 ΔE 0.066
- Lightblue #7BC8F6 ΔE 0.072
- Carolina Blue #8AB8FE ΔE 0.074
- Sky #82CAFC ΔE 0.082
- Dark Turquoise #00CED1 ΔE 0.086
Use #37B8EE 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.