#273D66
Closest named color: Prussian Blue (#1D3557). oklch(36.3% 0.077 261.9), rgb(39, 61, 102).
Aa
White text reads best on this color (10.79:1).
About this color
#273D66 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.077 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.037 away. White text reads best on it, at 10.79:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.077) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.94:1 |
| White text | 10.79:1 |
Values
| HEX | #273D66 |
| RGB | rgb(39, 61, 102) |
| HSL | hsl(219, 45%, 28%) |
| OKLCH | oklch(36.3% 0.077 261.9) |
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 #273D66 | 10.79:1 | AAA | Lc -98.8 | Preferred for body text |
| Black text on #273D66 | 1.94:1 | Fails | Lc 9.0 | Not readable |
| #273D66 text on white | 10.79:1 | AAA | Lc 94.9 | Preferred for body text |
| #273D66 text on black | 1.94:1 | Fails | Lc -7.8 | Not readable |
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 900.
-
Step 50
50
#F3F6FB
oklch(97.2% 0.007 260.7)
-
Step 100
100
#E4EAF5
oklch(93.6% 0.016 262.8)
-
Step 200
200
#CEDAEF
oklch(88.6% 0.032 261.7)
-
Step 300
300
#ADC1E7
oklch(80.9% 0.058 263.2)
-
Step 400
400
#81A1DA
oklch(70.7% 0.091 261.7)
-
Step 500
500
#6288D0
oklch(63% 0.117 262.4)
-
Step 600
600
#4871BD
oklch(55.5% 0.127 261.7)
-
Step 700
700
#3A5EA3
oklch(49% 0.118 262.2)
-
Step 800
800
#304D84
oklch(42.6% 0.098 262.1)
-
Step 900
900 (this color)
#273D66
oklch(36.3% 0.077 261.9)
-
Step 950
950
#19263E
oklch(27% 0.049 262)
#273D66 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) | #2C4168 | 0.015 |
| Deuteranopia (no green cones) | #243B65 | 0.008 |
| Tritanopia (no blue cones) | #00464C | 0.068 |
| Achromatopsia (no color) | #3D3D3D | 0.077 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #273D66
#273D66
oklch(36.3% 0.077 261.9)
- #513900
#513900
oklch(36.2% 0.075 82.1)
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 #273D66, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.037
- Marine Blue #01386A ΔE 0.038
- Dark Grey Blue #29465B ΔE 0.039
- Twilight Blue #0A437A ΔE 0.039
- Dark Blue Grey #1F3B4D ΔE 0.046
- Charcoal #264653 ΔE 0.050
- Midnight Green #073B4C ΔE 0.057
- Marine #042E60 ΔE 0.061
Use #273D66 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.