#313E87
Closest named color: Cobalt (#1E488F). oklch(39.5% 0.122 272), rgb(49, 62, 135).
Aa
White text reads best on this color (9.67:1).
About this color
#313E87 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.122 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 9.67:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.16:1 |
| White text | 9.67:1 |
Values
| HEX | #313E87 |
| RGB | rgb(49, 62, 135) |
| HSL | hsl(231, 47%, 36%) |
| OKLCH | oklch(39.5% 0.122 272) |
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 #313E87 | 9.67:1 | AAA | Lc -96.4 | Preferred for body text |
| Black text on #313E87 | 2.16:1 | Fails | Lc 11.8 | Not readable |
| #313E87 text on white | 9.67:1 | AAA | Lc 92.1 | Preferred for body text |
| #313E87 text on black | 2.16:1 | Fails | Lc -10.3 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FC
oklch(93.5% 0.027 271.9)
-
Step 200
200
#CDD8FC
oklch(88.5% 0.051 271.9)
-
Step 300
300
#ACBDFD
oklch(80.9% 0.093 272.7)
-
Step 400
400
#8199FB
oklch(70.7% 0.146 271.8)
-
Step 500
500
#647CF9
oklch(63.2% 0.187 271.8)
-
Step 600
600
#4E61E8
oklch(55.7% 0.203 271.9)
-
Step 700
700
#404FCA
oklch(49.2% 0.19 272.1)
-
Step 800
800
#3441A3
oklch(42.6% 0.158 272.1)
-
Step 900
900 (this color)
#313E87
oklch(39.5% 0.122 272)
-
Step 950
950
#1A224C
oklch(27.1% 0.078 272.1)
#313E87 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) | #11488A | 0.036 |
| Deuteranopia (no green cones) | #004185 | 0.039 |
| Tritanopia (no blue cones) | #004F5C | 0.104 |
| Achromatopsia (no color) | #444444 | 0.123 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313E87
#313E87
oklch(39.5% 0.122 272)
- #564400
#564400
oklch(39.4% 0.081 91.6)
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 #313E87, 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 0.036
- Blueberry #464196 ΔE 0.041
- Twilight Blue #0A437A ΔE 0.043
- Light Navy #155084 ΔE 0.054
- Dusk Blue #26538D ΔE 0.058
- Sapphire #2138AB ΔE 0.064
- Deep Sea Blue #015482 ΔE 0.068
Use #313E87 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.