#12397E
Closest named color: Twilight Blue (#0A437A). oklch(36.2% 0.125 260.9), rgb(18, 57, 126).
Aa
White text reads best on this color (10.98:1).
About this color
#12397E is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.125 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.030 away. White text reads best on it, at 10.98:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.91:1 |
| White text | 10.98:1 |
Values
| HEX | #12397E |
| RGB | rgb(18, 57, 126) |
| HSL | hsl(218, 75%, 28%) |
| OKLCH | oklch(36.2% 0.125 260.9) |
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 #12397E | 10.98:1 | AAA | Lc -98.8 | Preferred for body text |
| Black text on #12397E | 1.91:1 | Fails | Lc 9.0 | Not readable |
| #12397E text on white | 10.98:1 | AAA | Lc 94.9 | Preferred for body text |
| #12397E text on black | 1.91:1 | Fails | Lc -7.7 | 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
#E0EBFD
oklch(93.7% 0.027 260.3)
-
Step 200
200
#C6DAFC
oklch(88.4% 0.052 261.1)
-
Step 300
300
#9EC2FE
oklch(81% 0.094 260.4)
-
Step 400
400
#699FFD
oklch(70.7% 0.15 260.8)
-
Step 500
500
#4083FB
oklch(63% 0.192 261)
-
Step 600
600
#1F69EA
oklch(55.6% 0.208 260.9)
-
Step 700
700
#1156CC
oklch(49% 0.195 261)
-
Step 800
800
#1248A5
oklch(42.8% 0.16 260.8)
-
Step 900
900 (this color)
#12397E
oklch(36.2% 0.125 260.9)
-
Step 950
950
#0E254C
oklch(27.1% 0.078 260.3)
#12397E 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) | #044180 | 0.022 |
| Deuteranopia (no green cones) | #00387D | 0.011 |
| Tritanopia (no blue cones) | #004A55 | 0.097 |
| Achromatopsia (no color) | #3C3C3C | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #12397E
#12397E
oklch(36.2% 0.125 260.9)
- #523900
#523900
oklch(36.4% 0.075 81)
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 #12397E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.030
- Marine Blue #01386A ΔE 0.037
- Cobalt #1E488F ΔE 0.052
- Marine #042E60 ΔE 0.062
- Prussian Blue #1D3557 ΔE 0.067
- Light Navy #155084 ΔE 0.068
- Dark Slate Blue #483D8B ΔE 0.075
- Sapphire #2138AB ΔE 0.076
Use #12397E 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.