#123C5A
Closest named color: Prussian Blue (#1D3557). oklch(34.3% 0.07 243.8), rgb(18, 60, 90).
Aa
White text reads best on this color (11.54:1).
About this color
#123C5A is a dark, muted blue. In OKLCH its lightness is 34%, its chroma 0.070 and its hue 244°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.022 away. White text reads best on it, at 11.54:1.
| Hue family | Blues |
| Lightness | dark (34%) |
| Chroma | muted (0.070) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.81:1 |
| White text | 11.54:1 |
Values
| HEX | #123C5A |
| RGB | rgb(18, 60, 90) |
| HSL | hsl(205, 67%, 21%) |
| OKLCH | oklch(34.3% 0.07 243.8) |
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 #123C5A | 11.54:1 | AAA | Lc -100.0 | Preferred for body text |
| Black text on #123C5A | 1.81:1 | Fails | Lc 7.6 | Not readable |
| #123C5A text on white | 11.54:1 | AAA | Lc 96.3 | Preferred for body text |
| #123C5A text on black | 1.81:1 | Fails | Lc 0.0 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E2EBF3
oklch(93.6% 0.015 244.7)
-
Step 200
200
#CADCEB
oklch(88.6% 0.028 243.1)
-
Step 300
300
#A5C5E0
oklch(80.9% 0.052 243.9)
-
Step 400
400
#72A7D1
oklch(70.7% 0.083 243.2)
-
Step 500
500
#4A90C5
oklch(63.1% 0.107 243.5)
-
Step 600
600
#2979B2
oklch(55.5% 0.117 244.1)
-
Step 700
700
#1A6699
oklch(49.1% 0.108 243.7)
-
Step 800
800
#19537C
oklch(42.6% 0.09 244)
-
Step 900
900 (this color)
#123C5A
oklch(34.3% 0.07 243.8)
-
Step 950
950
#12293A
oklch(27.1% 0.043 242.6)
#123C5A 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) | #2E3D5B | 0.031 |
| Deuteranopia (no green cones) | #243659 | 0.024 |
| Tritanopia (no blue cones) | #004347 | 0.048 |
| Achromatopsia (no color) | #393939 | 0.070 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #123C5A
#123C5A
oklch(34.3% 0.07 243.8)
- #51300A
#51300A
oklch(34.3% 0.069 64.6)
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 #123C5A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.022
- Dark Blue Grey #1F3B4D ΔE 0.024
- Midnight Green #073B4C ΔE 0.027
- Marine Blue #01386A ΔE 0.034
- Dark Grey Blue #29465B ΔE 0.043
- Charcoal #264653 ΔE 0.045
- Marine #042E60 ΔE 0.050
- Gunmetal #293241 ΔE 0.050
Use #123C5A 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.