#042740
Closest named color: Oxford Blue (#1B263B). oklch(26.3% 0.061 244.8), rgb(4, 39, 64).
Aa
White text reads best on this color (15.33:1).
About this color
#042740 is a dark, muted blue. In OKLCH its lightness is 26%, its chroma 0.061 and its hue 245°. Its hue sits on the cool side of the wheel. The nearest named color is Oxford Blue (#1B263B), ΔE 0.025 away. White text reads best on it, at 15.33:1.
| Hue family | Blues |
| Lightness | dark (26%) |
| Chroma | muted (0.061) |
| Temperature | cool |
| Nearest name | Oxford Blue (#1B263B) |
| Black text | 1.36:1 |
| White text | 15.33:1 |
Values
| HEX | #042740 |
| RGB | rgb(4, 39, 64) |
| HSL | hsl(205, 88%, 13%) |
| OKLCH | oklch(26.3% 0.061 244.8) |
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 #042740 | 15.33:1 | AAA | Lc -104.8 | Preferred for body text |
| Black text on #042740 | 1.36:1 | Fails | Lc 0.0 | Not readable |
| #042740 text on white | 15.33:1 | AAA | Lc 102.0 | Preferred for body text |
| #042740 text on black | 1.36:1 | Fails | Lc 0.0 | 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 950.
-
Step 50
50
#F0F6FC
oklch(97% 0.01 247.9)
-
Step 100
100
#DFECF7
oklch(93.7% 0.02 243.4)
-
Step 200
200
#C4DDF2
oklch(88.6% 0.039 243.5)
-
Step 300
300
#9AC6EC
oklch(80.8% 0.071 244.9)
-
Step 400
400
#5DA8E3
oklch(70.7% 0.115 244.2)
-
Step 500
500
#2090DB
oklch(63% 0.147 244.6)
-
Step 600
600
#0079BE
oklch(55.6% 0.139 244.6)
-
Step 700
700
#0065A1
oklch(49% 0.124 245.1)
-
Step 800
800
#005385
oklch(42.7% 0.107 244.8)
-
Step 900
900
#004570
oklch(37.7% 0.095 244.9)
-
Step 950
950 (this color)
#042740
oklch(26.3% 0.061 244.8)
#042740 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) | #1B2841 | 0.025 |
| Deuteranopia (no green cones) | #122340 | 0.017 |
| Tritanopia (no blue cones) | #002D30 | 0.042 |
| Achromatopsia (no color) | #252525 | 0.061 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #042740
#042740
oklch(26.3% 0.061 244.8)
- #381E00
#381E00
oklch(26.4% 0.059 65.6)
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 #042740, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Oxford Blue #1B263B ΔE 0.025
- Dark #1B2431 ΔE 0.035
- Jet #212529 ΔE 0.051
- Rich Black #0D1B2A ΔE 0.052
- Space Cadet #2B2D42 ΔE 0.056
- Marine #042E60 ΔE 0.060
- Gunmetal #293241 ΔE 0.062
- Prussian Blue #1D3557 ΔE 0.066
Use #042740 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.