#63ADDD
Closest named color: Greyblue (#77A1B5). oklch(71.9% 0.102 238.8), rgb(99, 173, 221).
Aa
Black text reads best on this color (8.55:1).
About this color
#63ADDD is a medium-light, moderately saturated blue. In OKLCH its lightness is 72%, its chroma 0.102 and its hue 239°. Its hue sits on the cool side of the wheel. The nearest named color is Greyblue (#77A1B5), ΔE 0.059 away. Black text reads best on it, at 8.55:1.
| Hue family | Blues |
| Lightness | medium-light (72%) |
| Chroma | moderately saturated (0.102) |
| Temperature | cool |
| Nearest name | Greyblue (#77A1B5) |
| Black text | 8.55:1 |
| White text | 2.45:1 |
Values
| HEX | #63ADDD |
| RGB | rgb(99, 173, 221) |
| HSL | hsl(204, 64%, 63%) |
| OKLCH | oklch(71.9% 0.102 238.8) |
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 #63ADDD | 2.45:1 | Fails | Lc -53.1 | Large or bold text, headings |
| Black text on #63ADDD | 8.55:1 | AAA | Lc 55.9 | Large or bold text, headings |
| #63ADDD text on white | 2.45:1 | Fails | Lc 48.1 | Large or bold text, headings |
| #63ADDD text on black | 8.55:1 | AAA | Lc -53.9 | 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
#F0F6FB
oklch(97% 0.009 242.8)
-
Step 100
100
#DFECF5
oklch(93.6% 0.018 237.8)
-
Step 200
200
#C5DDEE
oklch(88.5% 0.035 238.7)
-
Step 300
300
#9BC7E6
oklch(80.9% 0.064 239.3)
-
Step 400
400 (this color)
#63ADDD
oklch(71.9% 0.102 238.8)
-
Step 500
500
#2493CF
oklch(63.2% 0.13 238.7)
-
Step 600
600
#007CB4
oklch(55.7% 0.125 238.6)
-
Step 700
700
#006898
oklch(49.2% 0.11 238.7)
-
Step 800
800
#00557D
oklch(42.7% 0.096 238.5)
-
Step 900
900
#004769
oklch(37.8% 0.084 238.3)
-
Step 950
950
#062A3E
oklch(27.1% 0.054 238.2)
#63ADDD 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) | #97ACDF | 0.057 |
| Deuteranopia (no green cones) | #87A0DC | 0.049 |
| Tritanopia (no blue cones) | #00B9BD | 0.081 |
| Achromatopsia (no color) | #A5A5A5 | 0.102 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #63ADDD
#63ADDD
oklch(71.9% 0.102 238.8)
- #D49461
#D49461
oklch(71.9% 0.102 58.7)
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 #63ADDD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Greyblue #77A1B5 ΔE 0.059
- Turquoise Blue #06B1C4 ΔE 0.064
- Deep Sky Blue #00BFFF ΔE 0.065
- Bluegrey #85A3B2 ΔE 0.066
- Carolina Blue #8AB8FE ΔE 0.070
- Bluey Grey #89A0B0 ΔE 0.072
- Vivid Sky Blue #4CC9F0 ΔE 0.074
- Cornflower Blue #6495ED ΔE 0.075
Use #63ADDD 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.