#63AACC
Closest named color: Greyblue (#77A1B5). oklch(70.4% 0.087 230.5), rgb(99, 170, 204).
Aa
Black text reads best on this color (8.15:1).
About this color
#63AACC is a medium-light, moderately saturated blue. In OKLCH its lightness is 70%, its chroma 0.087 and its hue 230°. Its hue sits on the cool side of the wheel. The nearest named color is Greyblue (#77A1B5), ΔE 0.038 away. Black text reads best on it, at 8.15:1.
| Hue family | Blues |
| Lightness | medium-light (70%) |
| Chroma | moderately saturated (0.087) |
| Temperature | cool |
| Nearest name | Greyblue (#77A1B5) |
| Black text | 8.15:1 |
| White text | 2.57:1 |
Values
| HEX | #63AACC |
| RGB | rgb(99, 170, 204) |
| HSL | hsl(199, 51%, 59%) |
| OKLCH | oklch(70.4% 0.087 230.5) |
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 #63AACC | 2.57:1 | Fails | Lc -55.4 | Large or bold text, headings |
| Black text on #63AACC | 8.15:1 | AAA | Lc 53.8 | Large or bold text, headings |
| #63AACC text on white | 2.57:1 | Fails | Lc 50.2 | Large or bold text, headings |
| #63AACC text on black | 8.15:1 | AAA | Lc -51.7 | 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
#F1F6F9
oklch(97% 0.007 233.6)
-
Step 100
100
#E0ECF3
oklch(93.6% 0.016 233)
-
Step 200
200
#C6DDEA
oklch(88.4% 0.03 232.5)
-
Step 300
300
#9DC8DE
oklch(80.9% 0.055 230.5)
-
Step 400
400 (this color)
#63AACC
oklch(70.4% 0.087 230.5)
-
Step 500
500
#2E95C0
oklch(63.1% 0.111 230.6)
-
Step 600
600
#007EA8
oklch(55.6% 0.112 230.6)
-
Step 700
700
#006A8E
oklch(49.1% 0.099 230.6)
-
Step 800
800
#005775
oklch(42.8% 0.086 230.3)
-
Step 900
900
#064861
oklch(37.7% 0.073 230.8)
-
Step 950
950
#092A39
oklch(26.9% 0.046 232.1)
#63AACC 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) | #99A8CE | 0.061 |
| Deuteranopia (no green cones) | #8A9CCC | 0.054 |
| Tritanopia (no blue cones) | #24B3B5 | 0.064 |
| Achromatopsia (no color) | #A1A1A1 | 0.087 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #63AACC
#63AACC
oklch(70.4% 0.087 230.5)
- #CC906E
#CC906E
oklch(70.4% 0.087 50.4)
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 #63AACC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Greyblue #77A1B5 ΔE 0.038
- Bluegrey #85A3B2 ΔE 0.048
- Turquoise Blue #06B1C4 ΔE 0.051
- Bluey Grey #89A0B0 ΔE 0.054
- Cool Steel #97A7B3 ΔE 0.064
- Cool Gray #8D99AE ΔE 0.065
- Cadet Blue #5F9EA0 ΔE 0.066
- Cool Grey #95A3A6 ΔE 0.072
Use #63AACC 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.