#63B4E5
Closest named color: Deep Sky Blue (#00BFFF). oklch(73.8% 0.107 237.2), rgb(99, 180, 229).
Aa
Black text reads best on this color (9.19:1).
About this color
#63B4E5 is a medium-light, moderately saturated blue. In OKLCH its lightness is 74%, its chroma 0.107 and its hue 237°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.051 away. Black text reads best on it, at 9.19:1.
| Hue family | Blues |
| Lightness | medium-light (74%) |
| Chroma | moderately saturated (0.107) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 9.19:1 |
| White text | 2.28:1 |
Values
| HEX | #63B4E5 |
| RGB | rgb(99, 180, 229) |
| HSL | hsl(203, 71%, 64%) |
| OKLCH | oklch(73.8% 0.107 237.2) |
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 #63B4E5 | 2.28:1 | Fails | Lc -49.7 | Large or bold text, headings |
| Black text on #63B4E5 | 9.19:1 | AAA | Lc 59.1 | Large or bold text, headings |
| #63B4E5 text on white | 2.28:1 | Fails | Lc 44.9 | Non-text elements, placeholder text |
| #63B4E5 text on black | 9.19:1 | AAA | Lc -57.2 | 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
#F0F6FB
oklch(97% 0.009 242.8)
-
Step 100
100
#DEECF5
oklch(93.5% 0.019 235.7)
-
Step 200
200
#C3DDEF
oklch(88.4% 0.037 238.1)
-
Step 300
300
#98C8E7
oklch(81% 0.067 237)
-
Step 400
400 (this color)
#63B4E5
oklch(73.8% 0.107 237.2)
-
Step 500
500
#0A94D1
oklch(63.2% 0.136 237)
-
Step 600
600
#007CB1
oklch(55.6% 0.122 237.2)
-
Step 700
700
#006896
oklch(49.1% 0.108 237.6)
-
Step 800
800
#00557B
oklch(42.6% 0.093 237.2)
-
Step 900
900
#004768
oklch(37.7% 0.083 237.5)
-
Step 950
950
#032A3E
oklch(27% 0.056 236.7)
#63B4E5 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) | #9DB3E7 | 0.063 |
| Deuteranopia (no green cones) | #8BA6E4 | 0.052 |
| Tritanopia (no blue cones) | #00C1C4 | 0.082 |
| Achromatopsia (no color) | #ABABAB | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #63B4E5
#63B4E5
oklch(73.8% 0.107 237.2)
- #DD9965
#DD9965
oklch(73.9% 0.106 57.6)
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 #63B4E5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.051
- Vivid Sky Blue #4CC9F0 ΔE 0.055
- Carolina Blue #8AB8FE ΔE 0.057
- Lightblue #7BC8F6 ΔE 0.063
- Bright Sky Blue #02CCFE ΔE 0.069
- Turquoise Blue #06B1C4 ΔE 0.071
- Light Grey Blue #9DBCD4 ΔE 0.073
- Sky #82CAFC ΔE 0.073
Use #63B4E5 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.