#63B9DF
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(74.7% 0.099 228.9), rgb(99, 185, 223).
Aa
Black text reads best on this color (9.53:1).
About this color
#63B9DF is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 75%, its chroma 0.099 and its hue 229°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.044 away. Black text reads best on it, at 9.53:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (75%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 9.53:1 |
| White text | 2.20:1 |
Values
| HEX | #63B9DF |
| RGB | rgb(99, 185, 223) |
| HSL | hsl(198, 66%, 63%) |
| OKLCH | oklch(74.7% 0.099 228.9) |
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 #63B9DF | 2.20:1 | Fails | Lc -47.9 | Large or bold text, headings |
| Black text on #63B9DF | 9.53:1 | AAA | Lc 60.8 | Content text, not long reading |
| #63B9DF text on white | 2.20:1 | Fails | Lc 43.2 | Non-text elements, placeholder text |
| #63B9DF text on black | 9.53:1 | AAA | Lc -59.0 | 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
#F0F7FA
oklch(97.2% 0.008 225.1)
-
Step 100
100
#DEECF4
oklch(93.5% 0.018 232.5)
-
Step 200
200
#C3DEEC
oklch(88.5% 0.035 230.3)
-
Step 300
300
#97C9E1
oklch(80.9% 0.062 229.1)
-
Step 400
400 (this color)
#63B9DF
oklch(74.7% 0.099 228.9)
-
Step 500
500
#0097C5
oklch(63.2% 0.124 228.7)
-
Step 600
600
#007EA6
oklch(55.5% 0.11 229.3)
-
Step 700
700
#006A8C
oklch(49% 0.097 229.1)
-
Step 800
800
#005773
oklch(42.7% 0.084 228.5)
-
Step 900
900
#004861
oklch(37.6% 0.075 229.8)
-
Step 950
950
#012B3B
oklch(27.1% 0.053 229.3)
#63B9DF 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) | #A5B6E1 | 0.071 |
| Deuteranopia (no green cones) | #94A9DF | 0.063 |
| Tritanopia (no blue cones) | #00C4C5 | 0.070 |
| Achromatopsia (no color) | #AFAFAF | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #63B9DF
#63B9DF
oklch(74.7% 0.099 228.9)
- #E09A74
#E09A74
oklch(74.6% 0.099 49.2)
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 #63B9DF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.044
- Deep Sky Blue #00BFFF ΔE 0.055
- Lightblue #7BC8F6 ΔE 0.055
- Light Cornflower Blue #98C1D9 ΔE 0.062
- Bright Sky Blue #02CCFE ΔE 0.062
- Light Grey Blue #9DBCD4 ΔE 0.063
- Carolina Blue #8AB8FE ΔE 0.063
- Sky #82CAFC ΔE 0.067
Use #63B9DF 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.