#1F3877
Closest named color: Twilight Blue (#0A437A). oklch(35.9% 0.112 265), rgb(31, 56, 119).
Aa
White text reads best on this color (11.10:1).
About this color
#1F3877 is a dark, moderately saturated blue. In OKLCH its lightness is 36%, its chroma 0.112 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.032 away. White text reads best on it, at 11.10:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.89:1 |
| White text | 11.10:1 |
Values
| HEX | #1F3877 |
| RGB | rgb(31, 56, 119) |
| HSL | hsl(223, 59%, 29%) |
| OKLCH | oklch(35.9% 0.112 265) |
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 #1F3877 | 11.10:1 | AAA | Lc -99.2 | Preferred for body text |
| Black text on #1F3877 | 1.89:1 | Fails | Lc 8.6 | Not readable |
| #1F3877 text on white | 11.10:1 | AAA | Lc 95.3 | Preferred for body text |
| #1F3877 text on black | 1.89:1 | Fails | Lc -7.3 | 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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFB
oklch(93.6% 0.025 265.6)
-
Step 200
200
#CAD9F9
oklch(88.4% 0.047 265.5)
-
Step 300
300
#A6C0F8
oklch(80.8% 0.085 265.2)
-
Step 400
400
#779EF5
oklch(70.8% 0.135 264.9)
-
Step 500
500
#5583F0
oklch(63.2% 0.171 264.7)
-
Step 600
600
#3B69DF
oklch(55.6% 0.187 264.8)
-
Step 700
700
#2E57C2
oklch(49.2% 0.174 264.8)
-
Step 800
800
#27479D
oklch(42.6% 0.145 265.3)
-
Step 900
900 (this color)
#1F3877
oklch(35.9% 0.112 265)
-
Step 950
950
#152449
oklch(27% 0.072 265.3)
#1F3877 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) | #124079 | 0.023 |
| Deuteranopia (no green cones) | #003876 | 0.022 |
| Tritanopia (no blue cones) | #004752 | 0.090 |
| Achromatopsia (no color) | #3C3C3C | 0.112 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F3877
#1F3877
oklch(35.9% 0.112 265)
- #4F3900
#4F3900
oklch(36% 0.074 84.3)
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 #1F3877, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.032
- Marine Blue #01386A ΔE 0.033
- Prussian Blue #1D3557 ΔE 0.056
- Marine #042E60 ΔE 0.056
- Cobalt #1E488F ΔE 0.057
- Light Navy #155084 ΔE 0.070
- Dark Slate Blue #483D8B ΔE 0.071
- Dark Grey Blue #29465B ΔE 0.073
Use #1F3877 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.