#1F3F8A
Closest named color: Cobalt (#1E488F). oklch(39% 0.131 263.9), rgb(31, 63, 138).
Aa
White text reads best on this color (9.83:1).
About this color
#1F3F8A is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.131 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.025 away. White text reads best on it, at 9.83:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.13:1 |
| White text | 9.83:1 |
Values
| HEX | #1F3F8A |
| RGB | rgb(31, 63, 138) |
| HSL | hsl(222, 63%, 33%) |
| OKLCH | oklch(39% 0.131 263.9) |
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 #1F3F8A | 9.83:1 | AAA | Lc -96.6 | Preferred for body text |
| Black text on #1F3F8A | 2.13:1 | Fails | Lc 11.6 | Not readable |
| #1F3F8A text on white | 9.83:1 | AAA | Lc 92.4 | Preferred for body text |
| #1F3F8A text on black | 2.13:1 | Fails | Lc -10.1 | 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
#F1F6FF
oklch(97.2% 0.013 262.4)
-
Step 100
100
#E0EAFE
oklch(93.6% 0.029 264.4)
-
Step 200
200
#C7DAFE
oklch(88.6% 0.054 263.2)
-
Step 300
300
#A1C0FF
oklch(80.8% 0.096 264.1)
-
Step 400
400
#6F9DFF
oklch(70.7% 0.152 263.9)
-
Step 500
500
#4980FF
oklch(63% 0.198 264)
-
Step 600
600
#2C65F0
oklch(55.6% 0.218 263.8)
-
Step 700
700
#2052D1
oklch(49% 0.203 263.9)
-
Step 800
800
#1C44A9
oklch(42.6% 0.168 264)
-
Step 900
900 (this color)
#1F3F8A
oklch(39% 0.131 263.9)
-
Step 950
950
#11234E
oklch(26.9% 0.083 264.4)
#1F3F8A 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) | #08498D | 0.028 |
| Deuteranopia (no green cones) | #003F89 | 0.019 |
| Tritanopia (no blue cones) | #00515E | 0.103 |
| Achromatopsia (no color) | #434343 | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F3F8A
#1F3F8A
oklch(39% 0.131 263.9)
- #594100
#594100
oklch(39.1% 0.08 84.7)
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 #1F3F8A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.025
- Twilight Blue #0A437A ΔE 0.034
- Light Navy #155084 ΔE 0.051
- Dark Slate Blue #483D8B ΔE 0.055
- Blueberry #464196 ΔE 0.056
- Sapphire #2138AB ΔE 0.057
- Dusk Blue #26538D ΔE 0.058
- Marine Blue #01386A ΔE 0.063
Use #1F3F8A 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.