#1F3B71
Closest named color: Twilight Blue (#0A437A). oklch(36.2% 0.099 262), rgb(31, 59, 113).
Aa
White text reads best on this color (10.92:1).
About this color
#1F3B71 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.099 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.027 away. White text reads best on it, at 10.92:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.92:1 |
| White text | 10.92:1 |
Values
| HEX | #1F3B71 |
| RGB | rgb(31, 59, 113) |
| HSL | hsl(220, 57%, 28%) |
| OKLCH | oklch(36.2% 0.099 262) |
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 #1F3B71 | 10.92:1 | AAA | Lc -98.9 | Preferred for body text |
| Black text on #1F3B71 | 1.92:1 | Fails | Lc 8.9 | Not readable |
| #1F3B71 text on white | 10.92:1 | AAA | Lc 95.0 | Preferred for body text |
| #1F3B71 text on black | 1.92:1 | Fails | Lc -7.6 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E2EAF9
oklch(93.5% 0.022 263.2)
-
Step 200
200
#CADAF5
oklch(88.5% 0.041 260.9)
-
Step 300
300
#A7C1F2
oklch(80.9% 0.075 262.9)
-
Step 400
400
#77A0EB
oklch(70.7% 0.119 261.9)
-
Step 500
500
#5586E5
oklch(63.1% 0.153 262.3)
-
Step 600
600
#3A6ED3
oklch(55.7% 0.166 262)
-
Step 700
700
#2C5BB6
oklch(49% 0.153 261.9)
-
Step 800
800
#264B94
oklch(42.8% 0.128 262.2)
-
Step 900
900 (this color)
#1F3B71
oklch(36.2% 0.099 262)
-
Step 950
950
#152545
oklch(26.9% 0.064 262.8)
#1F3B71 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) | #204173 | 0.018 |
| Deuteranopia (no green cones) | #103970 | 0.015 |
| Tritanopia (no blue cones) | #004850 | 0.081 |
| Achromatopsia (no color) | #3D3D3D | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F3B71
#1F3B71
oklch(36.2% 0.099 262)
- #513900
#513900
oklch(36.2% 0.075 82.1)
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 #1F3B71, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.027
- Marine Blue #01386A ΔE 0.028
- Prussian Blue #1D3557 ΔE 0.047
- Marine #042E60 ΔE 0.056
- Dark Grey Blue #29465B ΔE 0.059
- Cobalt #1E488F ΔE 0.059
- Dark Blue Grey #1F3B4D ΔE 0.064
- Light Navy #155084 ΔE 0.065
Use #1F3B71 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.