#1F4781
Closest named color: Twilight Blue (#0A437A). oklch(40.2% 0.108 258), rgb(31, 71, 129).
Aa
White text reads best on this color (9.22:1).
About this color
#1F4781 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.108 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.023 away. White text reads best on it, at 9.22:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.108) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.27:1 |
| White text | 9.22:1 |
Values
| HEX | #1F4781 |
| RGB | rgb(31, 71, 129) |
| HSL | hsl(216, 61%, 31%) |
| OKLCH | oklch(40.2% 0.108 258) |
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 #1F4781 | 9.22:1 | AAA | Lc -95.3 | Preferred for body text |
| Black text on #1F4781 | 2.27:1 | Fails | Lc 13.0 | Not readable |
| #1F4781 text on white | 9.22:1 | AAA | Lc 90.9 | Preferred for body text |
| #1F4781 text on black | 2.27:1 | Fails | Lc -11.4 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBFA
oklch(93.6% 0.024 256.1)
-
Step 200
200
#C7DBF7
oklch(88.5% 0.044 256.8)
-
Step 300
300
#A0C3F5
oklch(80.9% 0.081 257.3)
-
Step 400
400
#6CA2F0
oklch(70.8% 0.129 257.6)
-
Step 500
500
#4388EB
oklch(63.1% 0.165 257.8)
-
Step 600
600
#226FD9
oklch(55.6% 0.179 257.9)
-
Step 700
700
#135CBD
oklch(49.1% 0.167 258)
-
Step 800
800
#144C99
oklch(42.8% 0.138 258)
-
Step 900
900 (this color)
#1F4781
oklch(40.2% 0.108 258)
-
Step 950
950
#0F2647
oklch(27% 0.068 257.7)
#1F4781 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) | #2A4C83 | 0.020 |
| Deuteranopia (no green cones) | #184380 | 0.014 |
| Tritanopia (no blue cones) | #00555D | 0.086 |
| Achromatopsia (no color) | #474747 | 0.108 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F4781
#1F4781
oklch(40.2% 0.108 258)
- #614100
#614100
oklch(40.2% 0.084 77.1)
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 #1F4781, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.023
- Cobalt #1E488F ΔE 0.023
- Light Navy #155084 ΔE 0.026
- Deep Sea Blue #015482 ΔE 0.039
- Dusk Blue #26538D ΔE 0.040
- Dark Slate Blue #483D8B ΔE 0.060
- Light Navy Blue #2E5A88 ΔE 0.060
- Blueberry #464196 ΔE 0.063
Use #1F4781 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.