#4288CC
Closest named color: Water Blue (#0E87CC). oklch(61.3% 0.125 250), rgb(66, 136, 204).
Aa
Black text reads best on this color (5.62:1).
About this color
#4288CC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.125 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Water Blue (#0E87CC), ΔE 0.027 away. Black text reads best on it, at 5.62:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Water Blue (#0E87CC) |
| Black text | 5.62:1 |
| White text | 3.73:1 |
Values
| HEX | #4288CC |
| RGB | rgb(66, 136, 204) |
| HSL | hsl(210, 58%, 53%) |
| OKLCH | oklch(61.3% 0.125 250) |
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 #4288CC | 3.73:1 | AA large text | Lc -70.1 | Content text, not long reading |
| Black text on #4288CC | 5.62:1 | AA | Lc 39.5 | Non-text elements, placeholder text |
| #4288CC text on white | 3.73:1 | AA large text | Lc 64.6 | Content text, not long reading |
| #4288CC text on black | 5.62:1 | AA | Lc -37.0 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E1EBF6
oklch(93.6% 0.018 250.6)
-
Step 200
200
#C9DBEF
oklch(88.4% 0.034 251)
-
Step 300
300
#A3C4E7
oklch(80.8% 0.061 250.1)
-
Step 400
400
#70A5DC
oklch(70.7% 0.099 250.2)
-
Step 500
500 (this color)
#4288CC
oklch(61.3% 0.125 250)
-
Step 600
600
#2676BF
oklch(55.5% 0.136 250.2)
-
Step 700
700
#1763A5
oklch(49.1% 0.127 250.1)
-
Step 800
800
#175186
oklch(42.7% 0.106 250.3)
-
Step 900
900
#1A446B
oklch(37.8% 0.082 249.5)
-
Step 950
950
#11283F
oklch(27.1% 0.052 250.3)
#4288CC 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) | #6A8BCF | 0.043 |
| Deuteranopia (no green cones) | #577ECB | 0.031 |
| Tritanopia (no blue cones) | #0098A1 | 0.095 |
| Achromatopsia (no color) | #848484 | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4288CC
#4288CC
oklch(61.3% 0.125 250)
- #B37518
#B37518
oklch(61.3% 0.125 70.4)
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 #4288CC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Water Blue #0E87CC ΔE 0.027
- Cool Blue #4984B8 ΔE 0.030
- Steel Blue #4682B4 ΔE 0.037
- Dark Sky Blue #448EE4 ΔE 0.038
- Faded Blue #658CBB ΔE 0.046
- Off Blue #5684AE ΔE 0.046
- Windows Blue #3778BF ΔE 0.048
- Dusty Blue #5A86AD ΔE 0.050
Use #4288CC 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.