#04579A
Closest named color: Dusk Blue (#26538D). oklch(45.2% 0.129 251), rgb(4, 87, 154).
Aa
White text reads best on this color (7.40:1).
About this color
#04579A is a medium-dark, moderately saturated blue. In OKLCH its lightness is 45%, its chroma 0.129 and its hue 251°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.026 away. White text reads best on it, at 7.40:1.
| Hue family | Blues |
| Lightness | medium-dark (45%) |
| Chroma | moderately saturated (0.129) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.83:1 |
| White text | 7.40:1 |
Values
| HEX | #04579A |
| RGB | rgb(4, 87, 154) |
| HSL | hsl(207, 95%, 31%) |
| OKLCH | oklch(45.2% 0.129 251) |
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 #04579A | 7.40:1 | AAA | Lc -90.0 | Preferred for body text |
| Black text on #04579A | 2.83:1 | Fails | Lc 18.9 | Dividers and decoration only |
| #04579A text on white | 7.40:1 | AAA | Lc 85.1 | Fine for body text |
| #04579A text on black | 2.83:1 | Fails | Lc -16.9 | Dividers and decoration only |
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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF8
oklch(93.6% 0.021 252.5)
-
Step 200
200
#C5DCF5
oklch(88.5% 0.042 250.5)
-
Step 300
300
#9DC5F0
oklch(81% 0.075 250.6)
-
Step 400
400
#64A5E9
oklch(70.7% 0.121 250.9)
-
Step 500
500
#338DE3
oklch(63.2% 0.154 250.9)
-
Step 600
600
#0075CD
oklch(55.6% 0.161 250.9)
-
Step 700
700
#0062AE
oklch(49.1% 0.143 251.1)
-
Step 800
800 (this color)
#04579A
oklch(45.2% 0.129 251)
-
Step 900
900
#0C4375
oklch(37.8% 0.101 251.2)
-
Step 950
950
#0A2844
oklch(27.1% 0.063 250.1)
#04579A 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) | #345C9D | 0.036 |
| Deuteranopia (no green cones) | #175099 | 0.020 |
| Tritanopia (no blue cones) | #006771 | 0.093 |
| Achromatopsia (no color) | #555555 | 0.129 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #04579A
#04579A
oklch(45.2% 0.129 251)
- #774B00
#774B00
oklch(45.2% 0.097 71.2)
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 #04579A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.026
- Light Navy #155084 ΔE 0.038
- Deep Sea Blue #015482 ΔE 0.040
- Light Navy Blue #2E5A88 ΔE 0.040
- Denim Blue #3B5B92 ΔE 0.043
- Cobalt #1E488F ΔE 0.043
- Peacock Blue #016795 ΔE 0.050
- Dusky Blue #475F94 ΔE 0.061
Use #04579A 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.