#12377F
Closest named color: Twilight Blue (#0A437A). oklch(35.9% 0.129 261.9), rgb(18, 55, 127).
Aa
White text reads best on this color (11.17:1).
About this color
#12377F is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.129 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.036 away. White text reads best on it, at 11.17:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.129) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.87:1 |
| White text | 11.17:1 |
Values
| HEX | #12377F |
| RGB | rgb(18, 55, 127) |
| HSL | hsl(220, 75%, 28%) |
| OKLCH | oklch(35.9% 0.129 261.9) |
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 #12377F | 11.17:1 | AAA | Lc -99.1 | Preferred for body text |
| Black text on #12377F | 1.87:1 | Fails | Lc 8.6 | Not readable |
| #12377F text on white | 11.17:1 | AAA | Lc 95.3 | Preferred for body text |
| #12377F text on black | 1.87:1 | Fails | Lc -7.4 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E0EAFD
oklch(93.5% 0.028 263.4)
-
Step 200
200
#C6DAFE
oklch(88.5% 0.054 262.2)
-
Step 300
300
#9FC1FF
oklch(80.9% 0.096 262.2)
-
Step 400
400
#6A9EFF
oklch(70.6% 0.153 261.9)
-
Step 500
500
#4182FF
oklch(63.1% 0.198 261.8)
-
Step 600
600
#2167EE
oklch(55.5% 0.215 261.8)
-
Step 700
700
#1555D0
oklch(49.2% 0.2 261.9)
-
Step 800
800
#1446A8
oklch(42.7% 0.166 262)
-
Step 900
900 (this color)
#12377F
oklch(35.9% 0.129 261.9)
-
Step 950
950
#0E244E
oklch(27% 0.082 261.8)
#12377F 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) | #004082 | 0.025 |
| Deuteranopia (no green cones) | #00367E | 0.011 |
| Tritanopia (no blue cones) | #004955 | 0.100 |
| Achromatopsia (no color) | #3B3B3B | 0.129 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #12377F
#12377F
oklch(35.9% 0.129 261.9)
- #503800
#503800
oklch(35.9% 0.074 81.7)
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 #12377F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.036
- Marine Blue #01386A ΔE 0.039
- Cobalt #1E488F ΔE 0.056
- Marine #042E60 ΔE 0.061
- Prussian Blue #1D3557 ΔE 0.069
- Light Navy #155084 ΔE 0.073
- Royal #0C1793 ΔE 0.074
- Sapphire #2138AB ΔE 0.075
Use #12377F 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.