#304A99
Closest named color: Cobalt (#1E488F). oklch(43.4% 0.133 267), rgb(48, 74, 153).
Aa
White text reads best on this color (8.18:1).
About this color
#304A99 is a dark, moderately saturated blue. In OKLCH its lightness is 43%, its chroma 0.133 and its hue 267°. 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 8.18:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.133) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.56:1 |
| White text | 8.18:1 |
Values
| HEX | #304A99 |
| RGB | rgb(48, 74, 153) |
| HSL | hsl(225, 52%, 39%) |
| OKLCH | oklch(43.4% 0.133 267) |
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 #304A99 | 8.18:1 | AAA | Lc -92.6 | Preferred for body text |
| Black text on #304A99 | 2.56:1 | Fails | Lc 16.0 | Dividers and decoration only |
| #304A99 text on white | 8.18:1 | AAA | Lc 88.0 | Fine for body text |
| #304A99 text on black | 2.56:1 | Fails | Lc -14.2 | 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
#F2F5FD
oklch(97% 0.011 269.6)
-
Step 100
100
#E3EAF9
oklch(93.6% 0.022 265.8)
-
Step 200
200
#CCD9F7
oklch(88.5% 0.044 266.9)
-
Step 300
300
#AAC0F4
oklch(80.9% 0.078 266.8)
-
Step 400
400
#7E9DEE
oklch(70.6% 0.124 267.3)
-
Step 500
500
#5E83E9
oklch(63.2% 0.159 266.9)
-
Step 600
600
#466AD7
oklch(55.7% 0.172 266.9)
-
Step 700
700
#3857BA
oklch(49% 0.16 267.2)
-
Step 800
800 (this color)
#304A99
oklch(43.4% 0.133 267)
-
Step 900
900
#293D78
oklch(37.7% 0.104 267.2)
-
Step 950
950
#182446
oklch(26.9% 0.065 267.3)
#304A99 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) | #1C549C | 0.029 |
| Deuteranopia (no green cones) | #004B97 | 0.032 |
| Tritanopia (no blue cones) | #005D6A | 0.110 |
| Achromatopsia (no color) | #4F4F4F | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #304A99
#304A99
oklch(43.4% 0.133 267)
- #664D00
#664D00
oklch(43.5% 0.089 87.1)
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 #304A99, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.026
- Blueberry #464196 ΔE 0.035
- Dusk Blue #26538D ΔE 0.035
- Light Navy #155084 ΔE 0.047
- Dark Slate Blue #483D8B ΔE 0.048
- Twilight #4E518B ΔE 0.053
- Denim Blue #3B5B92 ΔE 0.055
- Light Navy Blue #2E5A88 ΔE 0.058
Use #304A99 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.