#288CB4
Closest named color: Blue NCS (#118AB2). oklch(60.2% 0.107 229.8), rgb(40, 140, 180).
Aa
Black text reads best on this color (5.50:1).
About this color
#288CB4 is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 60%, its chroma 0.107 and its hue 230°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.012 away. Black text reads best on it, at 5.50:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.107) |
| Temperature | cool |
| Nearest name | Blue NCS (#118AB2) |
| Black text | 5.50:1 |
| White text | 3.81:1 |
Values
| HEX | #288CB4 |
| RGB | rgb(40, 140, 180) |
| HSL | hsl(197, 64%, 43%) |
| OKLCH | oklch(60.2% 0.107 229.8) |
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 #288CB4 | 3.81:1 | AA large text | Lc -70.8 | Content text, not long reading |
| Black text on #288CB4 | 5.50:1 | AA | Lc 38.8 | Non-text elements, placeholder text |
| #288CB4 text on white | 3.81:1 | AA large text | Lc 65.3 | Content text, not long reading |
| #288CB4 text on black | 5.50:1 | AA | Lc -36.4 | 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
#F1F6F9
oklch(97% 0.007 233.6)
-
Step 100
100
#E0ECF2
oklch(93.6% 0.015 229)
-
Step 200
200
#C7DDE9
oklch(88.5% 0.029 231.5)
-
Step 300
300
#9FC8DC
oklch(81% 0.052 229.2)
-
Step 400
400
#66ABCB
oklch(70.8% 0.084 229.5)
-
Step 500
500 (this color)
#288CB4
oklch(60.2% 0.107 229.8)
-
Step 600
600
#007EA7
oklch(55.5% 0.111 230)
-
Step 700
700
#006A8D
oklch(49.1% 0.098 229.8)
-
Step 800
800
#005774
oklch(42.7% 0.085 229.4)
-
Step 900
900
#0B485F
oklch(37.7% 0.069 229.5)
-
Step 950
950
#0B2A38
oklch(27% 0.044 231.3)
#288CB4 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) | #778AB6 | 0.073 |
| Deuteranopia (no green cones) | #657DB3 | 0.063 |
| Tritanopia (no blue cones) | #009799 | 0.062 |
| Achromatopsia (no color) | #828282 | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #288CB4
#288CB4
oklch(60.2% 0.107 229.8)
- #B36C43
#B36C43
oklch(60.1% 0.107 49.7)
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 #288CB4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue NCS #118AB2 ΔE 0.012
- Cool Blue #4984B8 ΔE 0.032
- Steel Blue #4682B4 ΔE 0.033
- Teal Blue #01889F ΔE 0.037
- Off Blue #5684AE ΔE 0.038
- Dusty Blue #5A86AD ΔE 0.040
- Water Blue #0E87CC ΔE 0.044
- Cerulean #457B9D ΔE 0.053
Use #288CB4 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.