#287D9E
Closest named color: Cerulean (#457B9D). oklch(55.4% 0.094 228.3), rgb(40, 125, 158).
Aa
White text reads best on this color (4.64:1).
About this color
#287D9E is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 55%, its chroma 0.094 and its hue 228°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.022 away. White text reads best on it, at 4.64:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.094) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.51:1 |
| White text | 4.64:1 |
Values
| HEX | #287D9E |
| RGB | rgb(40, 125, 158) |
| HSL | hsl(197, 60%, 39%) |
| OKLCH | oklch(55.4% 0.094 228.3) |
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 #287D9E | 4.64:1 | AA | Lc -77.4 | Fine for body text |
| Black text on #287D9E | 4.51:1 | AA | Lc 32.1 | Non-text elements, placeholder text |
| #287D9E text on white | 4.64:1 | AA | Lc 72.0 | Content text, not long reading |
| #287D9E text on black | 4.51:1 | AA | Lc -29.7 | Dividers and decoration only |
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 600.
-
Step 50
50
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E2ECF0
oklch(93.7% 0.012 223.5)
-
Step 200
200
#CADDE6
oklch(88.6% 0.024 227.8)
-
Step 300
300
#A5C7D6
oklch(81% 0.042 226.4)
-
Step 400
400
#73A9C2
oklch(70.6% 0.067 228.7)
-
Step 500
500
#4B94B3
oklch(63.2% 0.086 228.2)
-
Step 600
600 (this color)
#287D9E
oklch(55.4% 0.094 228.3)
-
Step 700
700
#1A6A88
oklch(49.2% 0.087 228.5)
-
Step 800
800
#19566E
oklch(42.6% 0.072 228.6)
-
Step 900
900
#1C4759
oklch(37.6% 0.056 228.6)
-
Step 950
950
#122A34
oklch(27.1% 0.035 227.4)
#287D9E 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) | #6C7BA0 | 0.068 |
| Deuteranopia (no green cones) | #5C6F9E | 0.059 |
| Tritanopia (no blue cones) | #008688 | 0.052 |
| Achromatopsia (no color) | #747474 | 0.094 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #287D9E
#287D9E
oklch(55.4% 0.094 228.3)
- #9F6140
#9F6140
oklch(55.4% 0.094 48.1)
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 #287D9E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.022
- Ocean #017B92 ΔE 0.025
- Dull Blue #49759C ΔE 0.032
- Stormy Blue #507B9C ΔE 0.033
- Teal Blue #01889F ΔE 0.033
- Nice Blue #107AB0 ΔE 0.033
- Sea Blue #047495 ΔE 0.034
- Muted Blue #3B719F ΔE 0.037
Use #287D9E 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.