#63B9EE
Closest named color: Deep Sky Blue (#00BFFF). oklch(75.3% 0.113 237.9), rgb(99, 185, 238).
Aa
Black text reads best on this color (9.70:1).
About this color
#63B9EE is a medium-light, moderately saturated blue. In OKLCH its lightness is 75%, its chroma 0.113 and its hue 238°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.043 away. Black text reads best on it, at 9.70:1.
| Hue family | Blues |
| Lightness | medium-light (75%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 9.70:1 |
| White text | 2.16:1 |
Values
| HEX | #63B9EE |
| RGB | rgb(99, 185, 238) |
| HSL | hsl(203, 80%, 66%) |
| OKLCH | oklch(75.3% 0.113 237.9) |
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 #63B9EE | 2.16:1 | Fails | Lc -47.0 | Large or bold text, headings |
| Black text on #63B9EE | 9.70:1 | AAA | Lc 61.6 | Content text, not long reading |
| #63B9EE text on white | 2.16:1 | Fails | Lc 42.3 | Non-text elements, placeholder text |
| #63B9EE text on black | 9.70:1 | AAA | Lc -59.9 | 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
#F0F7FB
oklch(97.2% 0.009 232.4)
-
Step 100
100
#DEECF6
oklch(93.6% 0.02 238.7)
-
Step 200
200
#C2DEF0
oklch(88.6% 0.039 236.1)
-
Step 300
300
#96C8E9
oklch(80.9% 0.07 237.7)
-
Step 400
400 (this color)
#63B9EE
oklch(75.3% 0.113 237.9)
-
Step 500
500
#0093D3
oklch(63% 0.14 238.1)
-
Step 600
600
#007CB2
oklch(55.6% 0.123 237.7)
-
Step 700
700
#006897
oklch(49.1% 0.109 238.1)
-
Step 800
800
#00557C
oklch(42.7% 0.094 237.9)
-
Step 900
900
#004768
oklch(37.7% 0.083 237.5)
-
Step 950
950
#002A40
oklch(27% 0.06 237.8)
#63B9EE 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) | #A1B8F1 | 0.066 |
| Deuteranopia (no green cones) | #8EAAED | 0.055 |
| Tritanopia (no blue cones) | #00C7CB | 0.085 |
| Achromatopsia (no color) | #B0B0B0 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #63B9EE
#63B9EE
oklch(75.3% 0.113 237.9)
- #E59C64
#E59C64
oklch(75.3% 0.113 57.4)
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 #63B9EE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.043
- Vivid Sky Blue #4CC9F0 ΔE 0.044
- Carolina Blue #8AB8FE ΔE 0.047
- Lightblue #7BC8F6 ΔE 0.049
- Bright Sky Blue #02CCFE ΔE 0.056
- Sky #82CAFC ΔE 0.059
- Light Cornflower Blue #98C1D9 ΔE 0.068
- Light Sky Blue #87CEFA ΔE 0.070
Use #63B9EE 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.