#288BCA
Closest named color: Water Blue (#0E87CC). oklch(61.1% 0.13 242.1), rgb(40, 139, 202).
Aa
Black text reads best on this color (5.63:1).
About this color
#288BCA is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.130 and its hue 242°. Its hue sits on the cool side of the wheel. The nearest named color is Water Blue (#0E87CC), ΔE 0.017 away. Black text reads best on it, at 5.63:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.130) |
| Temperature | cool |
| Nearest name | Water Blue (#0E87CC) |
| Black text | 5.63:1 |
| White text | 3.72:1 |
Values
| HEX | #288BCA |
| RGB | rgb(40, 139, 202) |
| HSL | hsl(203, 67%, 47%) |
| OKLCH | oklch(61.1% 0.13 242.1) |
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 #288BCA | 3.72:1 | AA large text | Lc -69.9 | Content text, not long reading |
| Black text on #288BCA | 5.63:1 | AA | Lc 39.7 | Non-text elements, placeholder text |
| #288BCA text on white | 3.72:1 | AA large text | Lc 64.4 | Content text, not long reading |
| #288BCA text on black | 5.63:1 | AA | Lc -37.3 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E0ECF5
oklch(93.7% 0.018 240)
-
Step 200
200
#C6DDEF
oklch(88.6% 0.035 241.5)
-
Step 300
300
#9DC6E7
oklch(80.8% 0.064 242.9)
-
Step 400
400
#64A8DB
oklch(70.7% 0.102 242.5)
-
Step 500
500 (this color)
#288BCA
oklch(61.1% 0.13 242.1)
-
Step 600
600
#007AB9
oklch(55.5% 0.132 242.1)
-
Step 700
700
#00679D
oklch(49.2% 0.117 242)
-
Step 800
800
#005481
oklch(42.7% 0.101 241.9)
-
Step 900
900
#09466A
oklch(37.8% 0.084 241.7)
-
Step 950
950
#09293E
oklch(27% 0.054 241.8)
#288BCA 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) | #6D8CCD | 0.061 |
| Deuteranopia (no green cones) | #577EC9 | 0.047 |
| Tritanopia (no blue cones) | #009BA1 | 0.090 |
| Achromatopsia (no color) | #848484 | 0.130 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #288BCA
#288BCA
oklch(61.1% 0.13 242.1)
- #B96F1D
#B96F1D
oklch(61% 0.129 62.4)
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 #288BCA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Water Blue #0E87CC ΔE 0.017
- Cool Blue #4984B8 ΔE 0.034
- Steel Blue #4682B4 ΔE 0.039
- Blue NCS #118AB2 ΔE 0.039
- Dark Sky Blue #448EE4 ΔE 0.046
- Off Blue #5684AE ΔE 0.050
- Windows Blue #3778BF ΔE 0.052
- Dusty Blue #5A86AD ΔE 0.054
Use #288BCA 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.