#313D8E
Closest named color: Cobalt (#1E488F). oklch(39.9% 0.134 272.5), rgb(49, 61, 142).
Aa
White text reads best on this color (9.59:1).
About this color
#313D8E is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.134 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.032 away. White text reads best on it, at 9.59:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.134) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.18:1 |
| White text | 9.59:1 |
Values
| HEX | #313D8E |
| RGB | rgb(49, 61, 142) |
| HSL | hsl(232, 49%, 37%) |
| OKLCH | oklch(39.9% 0.134 272.5) |
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 #313D8E | 9.59:1 | AAA | Lc -96.1 | Preferred for body text |
| Black text on #313D8E | 2.18:1 | Fails | Lc 12.1 | Not readable |
| #313D8E text on white | 9.59:1 | AAA | Lc 91.9 | Preferred for body text |
| #313D8E text on black | 2.18:1 | Fails | Lc -10.5 | 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
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E3E9FE
oklch(93.6% 0.029 273.1)
-
Step 200
200
#CCD8FF
oklch(88.6% 0.055 271.8)
-
Step 300
300
#ABBDFF
oklch(80.9% 0.096 272.3)
-
Step 400
400
#8198FF
oklch(70.7% 0.153 272.5)
-
Step 500
500
#6479FF
oklch(63% 0.199 272.7)
-
Step 600
600
#4D5CF3
oklch(55.6% 0.224 272.4)
-
Step 700
700
#3F4AD3
oklch(49.1% 0.207 272.5)
-
Step 800
800
#343EAB
oklch(42.7% 0.172 272.7)
-
Step 900
900 (this color)
#313D8E
oklch(39.9% 0.134 272.5)
-
Step 950
950
#19214F
oklch(27% 0.085 272.1)
#313D8E 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) | #004991 | 0.043 |
| Deuteranopia (no green cones) | #00418C | 0.038 |
| Tritanopia (no blue cones) | #00505F | 0.112 |
| Achromatopsia (no color) | #454545 | 0.134 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313D8E
#313D8E
oklch(39.9% 0.134 272.5)
- #574500
#574500
oklch(39.8% 0.081 91.8)
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 #313D8E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.032
- Dark Slate Blue #483D8B ΔE 0.035
- Blueberry #464196 ΔE 0.037
- Twilight Blue #0A437A ΔE 0.052
- Sapphire #2138AB ΔE 0.053
- Light Navy #155084 ΔE 0.060
- Dusk Blue #26538D ΔE 0.061
- Deep Sea Blue #015482 ΔE 0.074
Use #313D8E 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.