#313F66
Closest named color: Dark Grey Blue (#29465B). oklch(37.5% 0.07 268), rgb(49, 63, 102).
Aa
White text reads best on this color (10.32:1).
About this color
#313F66 is a dark, muted blue. In OKLCH its lightness is 37%, its chroma 0.070 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.034 away. White text reads best on it, at 10.32:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | muted (0.070) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.03:1 |
| White text | 10.32:1 |
Values
| HEX | #313F66 |
| RGB | rgb(49, 63, 102) |
| HSL | hsl(224, 35%, 30%) |
| OKLCH | oklch(37.5% 0.07 268) |
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 #313F66 | 10.32:1 | AAA | Lc -97.9 | Preferred for body text |
| Black text on #313F66 | 2.03:1 | Fails | Lc 10.0 | Not readable |
| #313F66 text on white | 10.32:1 | AAA | Lc 93.9 | Preferred for body text |
| #313F66 text on black | 2.03:1 | Fails | Lc -8.7 | 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
#F3F5FA
oklch(97% 0.007 268.5)
-
Step 100
100
#E5EAF4
oklch(93.6% 0.015 264.5)
-
Step 200
200
#D1D9ED
oklch(88.5% 0.029 268.3)
-
Step 300
300
#B2C0E3
oklch(80.9% 0.052 268)
-
Step 400
400
#8A9FD5
oklch(70.7% 0.083 267.8)
-
Step 500
500
#6E86CA
oklch(63% 0.107 268.5)
-
Step 600
600
#566FB7
oklch(55.6% 0.116 268)
-
Step 700
700
#465D9E
oklch(49.2% 0.108 267.6)
-
Step 800
800
#3A4C80
oklch(42.7% 0.089 268.1)
-
Step 900
900 (this color)
#313F66
oklch(37.5% 0.07 268)
-
Step 950
950
#1D253C
oklch(26.9% 0.045 268.7)
#313F66 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) | #304368 | 0.012 |
| Deuteranopia (no green cones) | #2B3E65 | 0.009 |
| Tritanopia (no blue cones) | #1B474D | 0.063 |
| Achromatopsia (no color) | #404040 | 0.070 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313F66
#313F66
oklch(37.5% 0.07 268)
- #503E0B
#503E0B
oklch(37.3% 0.07 88)
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 #313F66, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.034
- Twilight Blue #0A437A ΔE 0.046
- Charcoal #264653 ΔE 0.047
- Prussian Blue #1D3557 ΔE 0.049
- Dark Blue Grey #1F3B4D ΔE 0.052
- Marine Blue #01386A ΔE 0.053
- Onyx #343A40 ΔE 0.064
- Light Navy #155084 ΔE 0.065
Use #313F66 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.