#304A88
Closest named color: Cobalt (#1E488F). oklch(42.2% 0.108 265), rgb(48, 74, 136).
Aa
White text reads best on this color (8.53:1).
About this color
#304A88 is a dark, moderately saturated blue. In OKLCH its lightness is 42%, its chroma 0.108 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.023 away. White text reads best on it, at 8.53:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | moderately saturated (0.108) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.46:1 |
| White text | 8.53:1 |
Values
| HEX | #304A88 |
| RGB | rgb(48, 74, 136) |
| HSL | hsl(222, 48%, 36%) |
| OKLCH | oklch(42.2% 0.108 265) |
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 #304A88 | 8.53:1 | AAA | Lc -93.7 | Preferred for body text |
| Black text on #304A88 | 2.46:1 | Fails | Lc 14.9 | Not readable |
| #304A88 text on white | 8.53:1 | AAA | Lc 89.1 | Fine for body text |
| #304A88 text on black | 2.46:1 | Fails | Lc -13.1 | 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 800.
-
Step 50
50
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E4EAF7
oklch(93.6% 0.019 266)
-
Step 200
200
#CED9F1
oklch(88.4% 0.035 266)
-
Step 300
300
#ADC1EA
oklch(81% 0.062 264.6)
-
Step 400
400
#829FE0
oklch(70.6% 0.101 265.5)
-
Step 500
500
#6386D7
oklch(63% 0.129 265.2)
-
Step 600
600
#4A6EC5
oklch(55.5% 0.141 265.2)
-
Step 700
700
#3C5CAA
oklch(49.1% 0.13 265.2)
-
Step 800
800 (this color)
#304A88
oklch(42.2% 0.108 265)
-
Step 900
900
#2B3F6E
oklch(37.6% 0.085 265.2)
-
Step 950
950
#192540
oklch(26.8% 0.053 264.9)
#304A88 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) | #2D518A | 0.020 |
| Deuteranopia (no green cones) | #1F4987 | 0.018 |
| Tritanopia (no blue cones) | #005862 | 0.091 |
| Achromatopsia (no color) | #4C4C4C | 0.108 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #304A88
#304A88
oklch(42.2% 0.108 265)
- #634900
#634900
oklch(42.2% 0.086 85.1)
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 #304A88, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.023
- Dusk Blue #26538D ΔE 0.026
- Light Navy #155084 ΔE 0.028
- Deep Sea Blue #015482 ΔE 0.042
- Blueberry #464196 ΔE 0.045
- Dark Slate Blue #483D8B ΔE 0.046
- Twilight Blue #0A437A ΔE 0.047
- Light Navy Blue #2E5A88 ΔE 0.047
Use #304A88 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.