#288AEC
Closest named color: Dark Sky Blue (#448EE4). oklch(62.9% 0.171 252.7), rgb(40, 138, 236).
Aa
Black text reads best on this color (5.93:1).
About this color
#288AEC is a medium-light, vivid blue. In OKLCH its lightness is 63%, its chroma 0.171 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.026 away. Black text reads best on it, at 5.93:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | vivid (0.171) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 5.93:1 |
| White text | 3.53:1 |
Values
| HEX | #288AEC |
| RGB | rgb(40, 138, 236) |
| HSL | hsl(210, 84%, 54%) |
| OKLCH | oklch(62.9% 0.171 252.7) |
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 #288AEC | 3.53:1 | AA large text | Lc -67.9 | Content text, not long reading |
| Black text on #288AEC | 5.93:1 | AA | Lc 41.6 | Non-text elements, placeholder text |
| #288AEC text on white | 3.53:1 | AA large text | Lc 62.4 | Content text, not long reading |
| #288AEC text on black | 5.93:1 | AA | Lc -39.3 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F0F6FD
oklch(97.1% 0.011 252.1)
-
Step 100
100
#DFEBFA
oklch(93.6% 0.024 254)
-
Step 200
200
#C4DCF8
oklch(88.6% 0.047 252.4)
-
Step 300
300
#9AC4F6
oklch(80.8% 0.084 253.2)
-
Step 400
400
#5FA4F2
oklch(70.7% 0.135 252.8)
-
Step 500
500 (this color)
#288AEC
oklch(62.9% 0.171 252.7)
-
Step 600
600
#0073D2
oklch(55.5% 0.17 252.7)
-
Step 700
700
#0061B2
oklch(49.2% 0.149 252.5)
-
Step 800
800
#004F93
oklch(42.7% 0.13 252.6)
-
Step 900
900
#04427A
oklch(37.7% 0.111 252.4)
-
Step 950
950
#072748
oklch(27% 0.071 252.7)
#288AEC 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) | #5992F0 | 0.045 |
| Deuteranopia (no green cones) | #3580EA | 0.026 |
| Tritanopia (no blue cones) | #00A1AF | 0.127 |
| Achromatopsia (no color) | #888888 | 0.171 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #288AEC
#288AEC
oklch(62.9% 0.171 252.7)
- #B97900
#B97900
oklch(62.8% 0.134 72.5)
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 #288AEC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.026
- Dodger Blue #1E90FF ΔE 0.030
- Chefchaouen Blue #4895EF ΔE 0.039
- Soft Blue #6488EA ΔE 0.048
- Water Blue #0E87CC ΔE 0.051
- Clear Blue #247AFD ΔE 0.051
- Cornflower Blue #6495ED ΔE 0.060
- Cornflower #6A79F7 ΔE 0.070
Use #288AEC 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.