#1F358D
Closest named color: Cobalt (#1E488F). oklch(37.2% 0.148 267.6), rgb(31, 53, 141).
Aa
White text reads best on this color (10.75:1).
About this color
#1F358D is a dark, vivid blue. In OKLCH its lightness is 37%, its chroma 0.148 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.050 away. White text reads best on it, at 10.75:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | vivid (0.148) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 1.95:1 |
| White text | 10.75:1 |
Values
| HEX | #1F358D |
| RGB | rgb(31, 53, 141) |
| HSL | hsl(228, 64%, 34%) |
| OKLCH | oklch(37.2% 0.148 267.6) |
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 #1F358D | 10.75:1 | AAA | Lc -98.3 | Preferred for body text |
| Black text on #1F358D | 1.95:1 | Fails | Lc 9.6 | Not readable |
| #1F358D text on white | 10.75:1 | AAA | Lc 94.4 | Preferred for body text |
| #1F358D text on black | 1.95:1 | Fails | Lc -8.2 | 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
#F1F5FF
oklch(97% 0.014 268.5)
-
Step 100
100
#E1EAFF
oklch(93.7% 0.03 267.2)
-
Step 200
200
#C9D9FF
oklch(88.6% 0.055 267.2)
-
Step 300
300
#A6BFFF
oklch(80.9% 0.095 267.8)
-
Step 400
400
#779BFF
oklch(70.7% 0.152 267.5)
-
Step 500
500
#567DFF
oklch(63% 0.198 267.8)
-
Step 600
600
#385CFF
oklch(55.7% 0.244 267.6)
-
Step 700
700
#2C49E0
oklch(49.2% 0.229 267.7)
-
Step 800
800
#243DB5
oklch(42.7% 0.191 267.7)
-
Step 900
900 (this color)
#1F358D
oklch(37.2% 0.148 267.6)
-
Step 950
950
#132153
oklch(27% 0.093 267.8)
#1F358D 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) | #004390 | 0.037 |
| Deuteranopia (no green cones) | #00398B | 0.021 |
| Tritanopia (no blue cones) | #004C5B | 0.118 |
| Achromatopsia (no color) | #3E3E3E | 0.148 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F358D
#1F358D
oklch(37.2% 0.148 267.6)
- #513D00
#513D00
oklch(37.2% 0.076 87.7)
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 #1F358D, closest first.
No curated palette has a color within ΔE 0.04 of #1F358D.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.050
- Sapphire #2138AB ΔE 0.050
- Twilight Blue #0A437A ΔE 0.052
- Dark Slate Blue #483D8B ΔE 0.065
- Marine Blue #01386A ΔE 0.065
- Royal #0C1793 ΔE 0.066
- Blueberry #464196 ΔE 0.068
- Light Navy #155084 ΔE 0.077
Use #1F358D 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.