#37A3FF
Closest named color: Chefchaouen Blue (#4895EF). oklch(69.8% 0.166 248.7), rgb(55, 163, 255).
Aa
Black text reads best on this color (7.84:1).
About this color
#37A3FF is a medium-light, vivid blue. In OKLCH its lightness is 70%, its chroma 0.166 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.039 away. Black text reads best on it, at 7.84:1.
| Hue family | Blues |
| Lightness | medium-light (70%) |
| Chroma | vivid (0.166) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 7.84:1 |
| White text | 2.67:1 |
Values
| HEX | #37A3FF |
| RGB | rgb(55, 163, 255) |
| HSL | hsl(208, 100%, 61%) |
| OKLCH | oklch(69.8% 0.166 248.7) |
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 #37A3FF | 2.67:1 | Fails | Lc -56.7 | Large or bold text, headings |
| Black text on #37A3FF | 7.84:1 | AAA | Lc 52.5 | Large or bold text, headings |
| #37A3FF text on white | 2.67:1 | Fails | Lc 51.6 | Large or bold text, headings |
| #37A3FF text on black | 7.84:1 | AAA | Lc -50.3 | 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
#EFF6FF
oklch(97% 0.014 254.6)
-
Step 100
100
#DBECFE
oklch(93.6% 0.03 249.7)
-
Step 200
200
#BCDDFE
oklch(88.4% 0.058 248.5)
-
Step 300
300
#8DC6FF
oklch(80.9% 0.1 249.2)
-
Step 400
400 (this color)
#37A3FF
oklch(69.8% 0.166 248.7)
-
Step 500
500
#008DEC
oklch(63.1% 0.173 248.9)
-
Step 600
600
#0077C7
oklch(55.7% 0.152 248.5)
-
Step 700
700
#0063A9
oklch(49% 0.136 249.1)
-
Step 800
800
#00518B
oklch(42.6% 0.117 248.8)
-
Step 900
900
#004475
oklch(37.8% 0.103 248.3)
-
Step 950
950
#002848
oklch(27% 0.073 248.1)
#37A3FF 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) | #78A8FF | 0.057 |
| Deuteranopia (no green cones) | #5A96FD | 0.038 |
| Tritanopia (no blue cones) | #00B9C5 | 0.120 |
| Achromatopsia (no color) | #9E9E9E | 0.166 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37A3FF
#37A3FF
oklch(69.8% 0.166 248.7)
- #DA8900
#DA8900
oklch(69.8% 0.153 68.6)
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 #37A3FF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.039
- Cornflower Blue #6495ED ΔE 0.048
- Dodger Blue #1E90FF ΔE 0.054
- Dark Sky Blue #448EE4 ΔE 0.062
- Soft Blue #6488EA ΔE 0.074
- Deep Sky Blue #00BFFF ΔE 0.075
- Periwinkle Blue #8F99FB ΔE 0.082
- Lavender Blue #8B88F8 ΔE 0.097
Use #37A3FF 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.