#288FB5
Closest named color: Blue NCS (#118AB2). oklch(61% 0.106 227.8), rgb(40, 143, 181).
Aa
Black text reads best on this color (5.68:1).
About this color
#288FB5 is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 61%, its chroma 0.106 and its hue 228°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.018 away. Black text reads best on it, at 5.68:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.106) |
| Temperature | cool |
| Nearest name | Blue NCS (#118AB2) |
| Black text | 5.68:1 |
| White text | 3.69:1 |
Values
| HEX | #288FB5 |
| RGB | rgb(40, 143, 181) |
| HSL | hsl(196, 64%, 43%) |
| OKLCH | oklch(61% 0.106 227.8) |
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 #288FB5 | 3.69:1 | AA large text | Lc -69.6 | Content text, not long reading |
| Black text on #288FB5 | 5.68:1 | AA | Lc 39.9 | Non-text elements, placeholder text |
| #288FB5 text on white | 3.69:1 | AA large text | Lc 64.1 | Content text, not long reading |
| #288FB5 text on black | 5.68:1 | AA | Lc -37.5 | 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
#C6DDE8
oklch(88.4% 0.029 228.1)
-
Step 300
300
#9EC8DB
oklch(80.9% 0.052 227.3)
-
Step 400
400
#65ABC9
oklch(70.6% 0.083 227.5)
-
Step 500
500 (this color)
#288FB5
oklch(61% 0.106 227.8)
-
Step 600
600
#007FA5
oklch(55.7% 0.108 227.8)
-
Step 700
700
#006A8B
oklch(49% 0.096 228.3)
-
Step 800
800
#005772
oklch(42.6% 0.083 227.6)
-
Step 900
900
#09485E
oklch(37.6% 0.069 228)
-
Step 950
950
#0A2A37
oklch(26.9% 0.044 228.8)
#288FB5 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) | #7B8CB7 | 0.077 |
| Deuteranopia (no green cones) | #687FB5 | 0.067 |
| Tritanopia (no blue cones) | #009A9C | 0.059 |
| Achromatopsia (no color) | #858585 | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #288FB5
#288FB5
oklch(61% 0.106 227.8)
- #B76E48
#B76E48
oklch(61% 0.107 47.5)
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 #288FB5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue NCS #118AB2 ΔE 0.018
- Cool Blue #4984B8 ΔE 0.038
- Steel Blue #4682B4 ΔE 0.039
- Teal Blue #01889F ΔE 0.040
- Off Blue #5684AE ΔE 0.042
- Dusty Blue #5A86AD ΔE 0.042
- Water Blue #0E87CC ΔE 0.048
- Faded Blue #658CBB ΔE 0.052
Use #288FB5 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.