#12398F
Closest named color: Cobalt (#1E488F). oklch(37.7% 0.149 262.9), rgb(18, 57, 143).
Aa
White text reads best on this color (10.46:1).
About this color
#12398F is a dark, vivid blue. In OKLCH its lightness is 38%, its chroma 0.149 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.044 away. White text reads best on it, at 10.46:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | vivid (0.149) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.00:1 |
| White text | 10.46:1 |
Values
| HEX | #12398F |
| RGB | rgb(18, 57, 143) |
| HSL | hsl(221, 78%, 32%) |
| OKLCH | oklch(37.7% 0.149 262.9) |
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 #12398F | 10.46:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #12398F | 2.00:1 | Fails | Lc 10.3 | Not readable |
| #12398F text on white | 10.46:1 | AAA | Lc 93.6 | Preferred for body text |
| #12398F text on black | 2.00:1 | Fails | Lc -8.9 | 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
#6D9EFF
oklch(70.8% 0.152 262.8)
-
Step 500
500
#4581FF
oklch(63.1% 0.198 262.9)
-
Step 600
600
#1960FF
oklch(55.5% 0.245 262.9)
-
Step 700
700
#0A4DE0
oklch(49.1% 0.231 262.9)
-
Step 800
800
#0C41B5
oklch(42.7% 0.191 262.8)
-
Step 900
900 (this color)
#12398F
oklch(37.7% 0.149 262.9)
-
Step 950
950
#0C2254
oklch(27% 0.095 263.4)
#12398F 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) | #004592 | 0.031 |
| Deuteranopia (no green cones) | #003A8D | 0.010 |
| Tritanopia (no blue cones) | #004F5E | 0.115 |
| Achromatopsia (no color) | #3F3F3F | 0.149 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #12398F
#12398F
oklch(37.7% 0.149 262.9)
- #553D00
#553D00
oklch(37.7% 0.077 83.5)
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 #12398F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.044
- Twilight Blue #0A437A ΔE 0.047
- Sapphire #2138AB ΔE 0.048
- Marine Blue #01386A ΔE 0.065
- Light Navy #155084 ΔE 0.070
- Royal #0C1793 ΔE 0.070
- Dark Slate Blue #483D8B ΔE 0.070
- Blueberry #464196 ΔE 0.071
Use #12398F 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.