#1F243F
Closest named color: Oxford Blue (#1B263B). oklch(27% 0.051 274.5), rgb(31, 36, 63).
Aa
White text reads best on this color (15.19:1).
About this color
#1F243F is a dark, muted blue. In OKLCH its lightness is 27%, its chroma 0.051 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Oxford Blue (#1B263B), ΔE 0.013 away. White text reads best on it, at 15.19:1.
| Hue family | Blues |
| Lightness | dark (27%) |
| Chroma | muted (0.051) |
| Temperature | cool |
| Nearest name | Oxford Blue (#1B263B) |
| Black text | 1.38:1 |
| White text | 15.19:1 |
Values
| HEX | #1F243F |
| RGB | rgb(31, 36, 63) |
| HSL | hsl(231, 34%, 18%) |
| OKLCH | oklch(27% 0.051 274.5) |
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 #1F243F | 15.19:1 | AAA | Lc -104.8 | Preferred for body text |
| Black text on #1F243F | 1.38:1 | Fails | Lc 0.0 | Not readable |
| #1F243F text on white | 15.19:1 | AAA | Lc 102.0 | Preferred for body text |
| #1F243F text on black | 1.38:1 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E6E9F6
oklch(93.6% 0.018 275.6)
-
Step 200
200
#D2D8F0
oklch(88.5% 0.034 274.5)
-
Step 300
300
#B4BEE8
oklch(80.8% 0.06 274.5)
-
Step 400
400
#8E9CDD
oklch(70.7% 0.097 274.3)
-
Step 500
500
#7482D3
oklch(63.1% 0.123 274.9)
-
Step 600
600
#5D6AC0
oklch(55.5% 0.133 274.7)
-
Step 700
700
#4D58A6
oklch(49.1% 0.124 274.8)
-
Step 800
800
#3F4886
oklch(42.6% 0.103 275)
-
Step 900
900
#353D6C
oklch(37.7% 0.081 274.6)
-
Step 950
950 (this color)
#1F243F
oklch(27% 0.051 274.5)
#1F243F 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) | #1A2740 | 0.011 |
| Deuteranopia (no green cones) | #18243E | 0.011 |
| Tritanopia (no blue cones) | #142A2E | 0.046 |
| Achromatopsia (no color) | #262626 | 0.051 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F243F
#1F243F
oklch(27% 0.051 274.5)
- #2E2604
#2E2604
oklch(27% 0.051 95.6)
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 #1F243F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Oxford Blue #1B263B ΔE 0.013
- Dark #1B2431 ΔE 0.028
- Space Cadet #2B2D42 ΔE 0.038
- Jet #212529 ΔE 0.043
- Gunmetal #293241 ΔE 0.051
- Rich Black #0D1B2A ΔE 0.057
- Prussian Blue #1D3557 ΔE 0.063
- Marine #042E60 ΔE 0.065
Use #1F243F 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.