#1F375D
Closest named color: Prussian Blue (#1D3557). oklch(33.8% 0.074 259.2), rgb(31, 55, 93).
Aa
White text reads best on this color (11.91:1).
About this color
#1F375D is a dark, moderately saturated blue. In OKLCH its lightness is 34%, its chroma 0.074 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.012 away. White text reads best on it, at 11.91:1.
| Hue family | Blues |
| Lightness | dark (34%) |
| Chroma | moderately saturated (0.074) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.76:1 |
| White text | 11.91:1 |
Values
| HEX | #1F375D |
| RGB | rgb(31, 55, 93) |
| HSL | hsl(217, 50%, 24%) |
| OKLCH | oklch(33.8% 0.074 259.2) |
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 #1F375D | 11.91:1 | AAA | Lc -100.7 | Preferred for body text |
| Black text on #1F375D | 1.76:1 | Fails | Lc 0.0 | Not readable |
| #1F375D text on white | 11.91:1 | AAA | Lc 97.1 | Preferred for body text |
| #1F375D text on black | 1.76:1 | Fails | Lc 0.0 | 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
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E4EAF5
oklch(93.6% 0.016 262.8)
-
Step 200
200
#CDDAEE
oklch(88.5% 0.031 258.9)
-
Step 300
300
#ACC2E5
oklch(80.9% 0.055 259.6)
-
Step 400
400
#7FA2D8
oklch(70.7% 0.089 258.9)
-
Step 500
500
#5F8ACD
oklch(63.1% 0.112 259)
-
Step 600
600
#4573BA
oklch(55.7% 0.122 258.8)
-
Step 700
700
#3760A1
oklch(49.2% 0.114 259.3)
-
Step 800
800
#2E4E82
oklch(42.6% 0.095 259.7)
-
Step 900
900 (this color)
#1F375D
oklch(33.8% 0.074 259.2)
-
Step 950
950
#18273D
oklch(27.1% 0.046 257.8)
#1F375D 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) | #273A5F | 0.015 |
| Deuteranopia (no green cones) | #1E345C | 0.010 |
| Tritanopia (no blue cones) | #004045 | 0.063 |
| Achromatopsia (no color) | #373737 | 0.074 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1F375D
#1F375D
oklch(33.8% 0.074 259.2)
- #4A3200
#4A3200
oklch(33.7% 0.07 79.3)
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 #1F375D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.012
- Marine Blue #01386A ΔE 0.030
- Dark Blue Grey #1F3B4D ΔE 0.034
- Marine #042E60 ΔE 0.040
- Midnight Green #073B4C ΔE 0.042
- Gunmetal #293241 ΔE 0.049
- Space Cadet #2B2D42 ΔE 0.052
- Dark Grey Blue #29465B ΔE 0.053
Use #1F375D 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.