#0A4173
Closest named color: Twilight Blue (#0A437A). oklch(37.1% 0.101 251.5), rgb(10, 65, 115).
Aa
White text reads best on this color (10.41:1).
About this color
#0A4173 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.101 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.013 away. White text reads best on it, at 10.41:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.101) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.01:1 |
| White text | 10.41:1 |
Values
| HEX | #0A4173 |
| RGB | rgb(10, 65, 115) |
| HSL | hsl(209, 84%, 25%) |
| OKLCH | oklch(37.1% 0.101 251.5) |
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 #0A4173 | 10.41:1 | AAA | Lc -97.8 | Preferred for body text |
| Black text on #0A4173 | 2.01:1 | Fails | Lc 10.2 | Not readable |
| #0A4173 text on white | 10.41:1 | AAA | Lc 93.7 | Preferred for body text |
| #0A4173 text on black | 2.01:1 | Fails | Lc -8.8 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF9
oklch(93.6% 0.022 254.4)
-
Step 200
200
#C5DCF5
oklch(88.5% 0.042 250.5)
-
Step 300
300
#9DC5F1
oklch(81% 0.076 251.2)
-
Step 400
400
#65A5EA
oklch(70.8% 0.121 251.5)
-
Step 500
500
#348CE3
oklch(63% 0.155 251.5)
-
Step 600
600
#0074CF
oklch(55.5% 0.165 251.7)
-
Step 700
700
#0062AF
oklch(49.2% 0.144 251.3)
-
Step 800
800
#005091
oklch(42.8% 0.126 251.5)
-
Step 900
900 (this color)
#0A4173
oklch(37.1% 0.101 251.5)
-
Step 950
950
#0A2744
oklch(26.8% 0.064 251.5)
#0A4173 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) | #284575 | 0.029 |
| Deuteranopia (no green cones) | #153C72 | 0.015 |
| Tritanopia (no blue cones) | #004D54 | 0.074 |
| Achromatopsia (no color) | #404040 | 0.101 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #0A4173
#0A4173
oklch(37.1% 0.101 251.5)
- #5A3800
#5A3800
oklch(37.2% 0.08 71.7)
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 #0A4173, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.013
- Marine Blue #01386A ΔE 0.031
- Light Navy #155084 ΔE 0.052
- Cobalt #1E488F ΔE 0.053
- Dark Grey Blue #29465B ΔE 0.053
- Prussian Blue #1D3557 ΔE 0.055
- Deep Sea Blue #015482 ΔE 0.059
- Charcoal #264653 ΔE 0.064
Use #0A4173 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.