#0F378B
Closest named color: Twilight Blue (#0A437A). oklch(36.8% 0.147 262.5), rgb(15, 55, 139).
Aa
White text reads best on this color (10.82:1).
About this color
#0F378B is a dark, vivid blue. In OKLCH its lightness is 37%, its chroma 0.147 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.046 away. White text reads best on it, at 10.82:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | vivid (0.147) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.93:1 |
| White text | 10.82:1 |
Values
| HEX | #0F378B |
| RGB | rgb(15, 55, 139) |
| HSL | hsl(221, 81%, 30%) |
| OKLCH | oklch(36.8% 0.147 262.5) |
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 #0F378B | 10.82:1 | AAA | Lc -98.4 | Preferred for body text |
| Black text on #0F378B | 1.93:1 | Fails | Lc 9.5 | Not readable |
| #0F378B text on white | 10.82:1 | AAA | Lc 94.4 | Preferred for body text |
| #0F378B text on black | 1.93:1 | Fails | Lc -8.2 | 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
#F1F6FF
oklch(97.2% 0.013 262.4)
-
Step 100
100
#DFEAFF
oklch(93.5% 0.031 263.5)
-
Step 200
200
#C6DAFF
oklch(88.5% 0.056 262.8)
-
Step 300
300
#A0C1FF
oklch(80.9% 0.095 262.7)
-
Step 400
400
#6C9EFF
oklch(70.7% 0.152 262.5)
-
Step 500
500
#4481FF
oklch(63% 0.198 262.7)
-
Step 600
600
#1561FF
oklch(55.6% 0.245 262.5)
-
Step 700
700
#074EDE
oklch(49% 0.227 262.5)
-
Step 800
800
#0B42B4
oklch(42.8% 0.188 262.5)
-
Step 900
900 (this color)
#0F378B
oklch(36.8% 0.147 262.5)
-
Step 950
950
#0B2353
oklch(27.1% 0.093 262.2)
#0F378B 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) | #00438E | 0.031 |
| Deuteranopia (no green cones) | #003889 | 0.008 |
| Tritanopia (no blue cones) | #004D5B | 0.114 |
| Achromatopsia (no color) | #3D3D3D | 0.147 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #0F378B
#0F378B
oklch(36.8% 0.147 262.5)
- #533B00
#533B00
oklch(36.9% 0.076 82.8)
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 #0F378B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.046
- Cobalt #1E488F ΔE 0.050
- Sapphire #2138AB ΔE 0.056
- Marine Blue #01386A ΔE 0.058
- Royal #0C1793 ΔE 0.066
- Light Navy #155084 ΔE 0.074
- Dark Slate Blue #483D8B ΔE 0.075
- Blueberry #464196 ΔE 0.077
Use #0F378B 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.