#043A8E
Closest named color: Twilight Blue (#0A437A). oklch(37.5% 0.149 260.2), rgb(4, 58, 142).
Aa
White text reads best on this color (10.49:1).
About this color
#043A8E is a dark, vivid blue. In OKLCH its lightness is 38%, its chroma 0.149 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.044 away. White text reads best on it, at 10.49:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | vivid (0.149) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.00:1 |
| White text | 10.49:1 |
Values
| HEX | #043A8E |
| RGB | rgb(4, 58, 142) |
| HSL | hsl(217, 95%, 29%) |
| OKLCH | oklch(37.5% 0.149 260.2) |
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 #043A8E | 10.49:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #043A8E | 2.00:1 | Fails | Lc 10.4 | Not readable |
| #043A8E text on white | 10.49:1 | AAA | Lc 93.6 | Preferred for body text |
| #043A8E text on black | 2.00:1 | Fails | Lc -8.9 | 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
#F0F6FF
oklch(97.1% 0.014 258.3)
-
Step 100
100
#DEEBFF
oklch(93.6% 0.031 258.9)
-
Step 200
200
#C4DAFF
oklch(88.4% 0.057 260.8)
-
Step 300
300
#9DC2FF
oklch(81% 0.096 260.2)
-
Step 400
400
#669FFF
oklch(70.7% 0.154 260.3)
-
Step 500
500
#3983FF
oklch(63.1% 0.199 260.2)
-
Step 600
600
#0066F6
oklch(55.6% 0.23 260.3)
-
Step 700
700
#0055D0
oklch(49% 0.203 260.3)
-
Step 800
800
#0046AD
oklch(42.8% 0.176 260.1)
-
Step 900
900 (this color)
#043A8E
oklch(37.5% 0.149 260.2)
-
Step 950
950
#072353
oklch(26.9% 0.094 260.5)
#043A8E 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) | #004591 | 0.030 |
| Deuteranopia (no green cones) | #003A8C | 0.004 |
| Tritanopia (no blue cones) | #00505E | 0.114 |
| Achromatopsia (no color) | #3F3F3F | 0.149 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #043A8E
#043A8E
oklch(37.5% 0.149 260.2)
- #563C00
#563C00
oklch(37.6% 0.078 81.1)
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 #043A8E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.044
- Cobalt #1E488F ΔE 0.045
- Sapphire #2138AB ΔE 0.052
- Marine Blue #01386A ΔE 0.062
- Light Navy #155084 ΔE 0.069
- Royal #0C1793 ΔE 0.071
- Blueberry #464196 ΔE 0.076
- Dark Slate Blue #483D8B ΔE 0.076
Use #043A8E 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.