#123D7C
Closest named color: Twilight Blue (#0A437A). oklch(37% 0.117 258.6), rgb(18, 61, 124).
Aa
White text reads best on this color (10.58:1).
About this color
#123D7C is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.117 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.018 away. White text reads best on it, at 10.58:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.117) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.98:1 |
| White text | 10.58:1 |
Values
| HEX | #123D7C |
| RGB | rgb(18, 61, 124) |
| HSL | hsl(216, 75%, 28%) |
| OKLCH | oklch(37% 0.117 258.6) |
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 #123D7C | 10.58:1 | AAA | Lc -98.1 | Preferred for body text |
| Black text on #123D7C | 1.98:1 | Fails | Lc 9.8 | Not readable |
| #123D7C text on white | 10.58:1 | AAA | Lc 94.1 | Preferred for body text |
| #123D7C text on black | 1.98:1 | Fails | Lc -8.5 | 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
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C6DBFA
oklch(88.6% 0.048 258)
-
Step 300
300
#9EC2FA
oklch(80.8% 0.089 259.1)
-
Step 400
400
#68A1F7
oklch(70.7% 0.14 258.4)
-
Step 500
500
#3D86F4
oklch(63.1% 0.18 258.7)
-
Step 600
600
#186DE2
oklch(55.6% 0.194 258.5)
-
Step 700
700
#075AC5
oklch(49.1% 0.182 258.6)
-
Step 800
800
#0D4A9F
oklch(42.7% 0.15 258.7)
-
Step 900
900 (this color)
#123D7C
oklch(37% 0.117 258.6)
-
Step 950
950
#0D254A
oklch(26.9% 0.075 258.9)
#123D7C 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) | #17447E | 0.022 |
| Deuteranopia (no green cones) | #003A7B | 0.014 |
| Tritanopia (no blue cones) | #004C56 | 0.090 |
| Achromatopsia (no color) | #3F3F3F | 0.117 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #123D7C
#123D7C
oklch(37% 0.117 258.6)
- #553A00
#553A00
oklch(37% 0.077 79.3)
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 #123D7C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.018
- Marine Blue #01386A ΔE 0.036
- Cobalt #1E488F ΔE 0.045
- Light Navy #155084 ΔE 0.057
- Prussian Blue #1D3557 ΔE 0.065
- Marine #042E60 ΔE 0.066
- Deep Sea Blue #015482 ΔE 0.067
- Dark Grey Blue #29465B ΔE 0.072
Use #123D7C 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.