#288FED
Closest named color: Dark Sky Blue (#448EE4). oklch(64% 0.167 250.9), rgb(40, 143, 237).
Aa
Black text reads best on this color (6.24:1).
About this color
#288FED is a medium-light, vivid blue. In OKLCH its lightness is 64%, its chroma 0.167 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.020 away. Black text reads best on it, at 6.24:1.
| Hue family | Blues |
| Lightness | medium-light (64%) |
| Chroma | vivid (0.167) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.24:1 |
| White text | 3.36:1 |
Values
| HEX | #288FED |
| RGB | rgb(40, 143, 237) |
| HSL | hsl(209, 85%, 54%) |
| OKLCH | oklch(64% 0.167 250.9) |
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 #288FED | 3.36:1 | AA large text | Lc -66.0 | Content text, not long reading |
| Black text on #288FED | 6.24:1 | AA | Lc 43.5 | Non-text elements, placeholder text |
| #288FED text on white | 3.36:1 | AA large text | Lc 60.6 | Content text, not long reading |
| #288FED text on black | 6.24:1 | AA | Lc -41.1 | 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
#C4DCF7
oklch(88.5% 0.045 251.4)
-
Step 300
300
#99C5F4
oklch(80.9% 0.082 250.5)
-
Step 400
400
#5EA5EF
oklch(70.7% 0.131 251)
-
Step 500
500 (this color)
#288FED
oklch(64% 0.167 250.9)
-
Step 600
600
#0075CD
oklch(55.6% 0.161 250.9)
-
Step 700
700
#0062AE
oklch(49.1% 0.143 251.1)
-
Step 800
800
#005090
oklch(42.7% 0.125 251.1)
-
Step 900
900
#004379
oklch(37.8% 0.109 250.7)
-
Step 950
950
#062747
oklch(26.9% 0.07 251.5)
#288FED 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) | #6195F1 | 0.049 |
| Deuteranopia (no green cones) | #4084EB | 0.029 |
| Tritanopia (no blue cones) | #00A6B2 | 0.124 |
| Achromatopsia (no color) | #8C8C8C | 0.167 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #288FED
#288FED
oklch(64% 0.167 250.9)
- #C07B00
#C07B00
oklch(64% 0.138 70.6)
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 #288FED, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.020
- Dodger Blue #1E90FF ΔE 0.027
- Chefchaouen Blue #4895EF ΔE 0.028
- Soft Blue #6488EA ΔE 0.047
- Cornflower Blue #6495ED ΔE 0.051
- Water Blue #0E87CC ΔE 0.054
- Clear Blue #247AFD ΔE 0.063
- Cornflower #6A79F7 ΔE 0.076
Use #288FED 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.