#304187
Closest named color: Cobalt (#1E488F). oklch(40.1% 0.118 270.1), rgb(48, 65, 135).
Aa
White text reads best on this color (9.41:1).
About this color
#304187 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.118 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.026 away. White text reads best on it, at 9.41:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.118) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.23:1 |
| White text | 9.41:1 |
Values
| HEX | #304187 |
| RGB | rgb(48, 65, 135) |
| HSL | hsl(228, 48%, 36%) |
| OKLCH | oklch(40.1% 0.118 270.1) |
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 #304187 | 9.41:1 | AAA | Lc -95.8 | Preferred for body text |
| Black text on #304187 | 2.23:1 | Fails | Lc 12.5 | Not readable |
| #304187 text on white | 9.41:1 | AAA | Lc 91.5 | Preferred for body text |
| #304187 text on black | 2.23:1 | Fails | Lc -10.9 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FC
oklch(93.5% 0.027 271.9)
-
Step 200
200
#CCD8FB
oklch(88.4% 0.05 270.4)
-
Step 300
300
#AABEFB
oklch(80.8% 0.089 270.3)
-
Step 400
400
#7E9AF9
oklch(70.6% 0.143 270)
-
Step 500
500
#607EF6
oklch(63.1% 0.182 270)
-
Step 600
600
#4963E5
oklch(55.5% 0.198 270.1)
-
Step 700
700
#3B51C7
oklch(49% 0.184 270.1)
-
Step 800
800
#3143A1
oklch(42.7% 0.153 270.3)
-
Step 900
900 (this color)
#304187
oklch(40.1% 0.118 270.1)
-
Step 950
950
#19234B
oklch(27.1% 0.075 270.2)
#304187 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) | #1A4A8A | 0.030 |
| Deuteranopia (no green cones) | #044386 | 0.034 |
| Tritanopia (no blue cones) | #00515D | 0.101 |
| Achromatopsia (no color) | #464646 | 0.119 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #304187
#304187
oklch(40.1% 0.118 270.1)
- #594500
#594500
oklch(40% 0.082 89.8)
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 #304187, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.026
- Dark Slate Blue #483D8B ΔE 0.037
- Twilight Blue #0A437A ΔE 0.041
- Blueberry #464196 ΔE 0.041
- Light Navy #155084 ΔE 0.047
- Dusk Blue #26538D ΔE 0.050
- Deep Sea Blue #015482 ΔE 0.061
- Twilight #4E518B ΔE 0.066
Use #304187 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.