#304B88
Closest named color: Dusk Blue (#26538D). oklch(42.4% 0.107 264.4), rgb(48, 75, 136).
Aa
White text reads best on this color (8.44:1).
About this color
#304B88 is a dark, moderately saturated blue. In OKLCH its lightness is 42%, its chroma 0.107 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.023 away. White text reads best on it, at 8.44:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | moderately saturated (0.107) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.48:1 |
| White text | 8.44:1 |
Values
| HEX | #304B88 |
| RGB | rgb(48, 75, 136) |
| HSL | hsl(222, 48%, 36%) |
| OKLCH | oklch(42.4% 0.107 264.4) |
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 #304B88 | 8.44:1 | AAA | Lc -93.4 | Preferred for body text |
| Black text on #304B88 | 2.48:1 | Fails | Lc 15.1 | Dividers and decoration only |
| #304B88 text on white | 8.44:1 | AAA | Lc 88.9 | Fine for body text |
| #304B88 text on black | 2.48:1 | Fails | Lc -13.3 | 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
#E4EAF6
oklch(93.6% 0.017 264.5)
-
Step 200
200
#CED9F1
oklch(88.4% 0.035 266)
-
Step 300
300
#ADC1EA
oklch(81% 0.062 264.6)
-
Step 400
400
#81A0DF
oklch(70.7% 0.099 263.9)
-
Step 500
500
#6287D6
oklch(63.1% 0.127 264.1)
-
Step 600
600
#496FC4
oklch(55.6% 0.139 264.2)
-
Step 700
700
#3B5CA9
oklch(49% 0.129 264.6)
-
Step 800
800 (this color)
#304B88
oklch(42.4% 0.107 264.4)
-
Step 900
900
#2B406E
oklch(37.8% 0.083 264.3)
-
Step 950
950
#192640
oklch(27.1% 0.052 263.2)
#304B88 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) | #2F518A | 0.017 |
| Deuteranopia (no green cones) | #214987 | 0.017 |
| Tritanopia (no blue cones) | #005963 | 0.090 |
| Achromatopsia (no color) | #4D4D4D | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #304B88
#304B88
oklch(42.4% 0.107 264.4)
- #644900
#644900
oklch(42.3% 0.087 84.2)
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 #304B88, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.023
- Cobalt #1E488F ΔE 0.024
- Light Navy #155084 ΔE 0.027
- Deep Sea Blue #015482 ΔE 0.040
- Light Navy Blue #2E5A88 ΔE 0.044
- Blueberry #464196 ΔE 0.046
- Twilight #4E518B ΔE 0.046
- Dark Slate Blue #483D8B ΔE 0.048
Use #304B88 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.