#31387F
Closest named color: Dark Slate Blue (#483D8B). oklch(37.7% 0.119 274.9), rgb(49, 56, 127).
Aa
White text reads best on this color (10.48:1).
About this color
#31387F is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.119 and its hue 275°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.045 away. White text reads best on it, at 10.48:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.119) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.00:1 |
| White text | 10.48:1 |
Values
| HEX | #31387F |
| RGB | rgb(49, 56, 127) |
| HSL | hsl(235, 44%, 35%) |
| OKLCH | oklch(37.7% 0.119 274.9) |
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 #31387F | 10.48:1 | AAA | Lc -98.1 | Preferred for body text |
| Black text on #31387F | 2.00:1 | Fails | Lc 9.9 | Not readable |
| #31387F text on white | 10.48:1 | AAA | Lc 94.0 | Preferred for body text |
| #31387F text on black | 2.00:1 | Fails | Lc -8.5 | 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
#F3F5FE
oklch(97.1% 0.012 276.1)
-
Step 100
100
#E4E9FC
oklch(93.6% 0.026 274.1)
-
Step 200
200
#CFD7FB
oklch(88.5% 0.05 275.4)
-
Step 300
300
#AFBDFB
oklch(81% 0.089 274.4)
-
Step 400
400
#8798F8
oklch(70.7% 0.141 274.6)
-
Step 500
500
#6C7AF5
oklch(63% 0.182 275)
-
Step 600
600
#5660E4
oklch(55.7% 0.197 274.7)
-
Step 700
700
#474EC6
oklch(49.1% 0.184 274.8)
-
Step 800
800
#3A41A0
oklch(42.7% 0.152 274.8)
-
Step 900
900 (this color)
#31387F
oklch(37.7% 0.119 274.9)
-
Step 950
950
#1C224A
oklch(27% 0.074 274)
#31387F 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) | #094381 | 0.042 |
| Deuteranopia (no green cones) | #003C7E | 0.042 |
| Tritanopia (no blue cones) | #004956 | 0.103 |
| Achromatopsia (no color) | #3F3F3F | 0.119 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #31387F
#31387F
oklch(37.7% 0.119 274.9)
- #4E4000
#4E4000
oklch(37.5% 0.077 94.9)
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 #31387F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.045
- Twilight Blue #0A437A ΔE 0.045
- Cobalt #1E488F ΔE 0.049
- Blueberry #464196 ΔE 0.056
- Marine Blue #01386A ΔE 0.059
- Light Navy #155084 ΔE 0.068
- Sapphire #2138AB ΔE 0.075
- Dusk Blue #26538D ΔE 0.076
Use #31387F 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.