#313B9E
Closest named color: Sapphire (#2138AB). oklch(40.9% 0.159 272.7), rgb(49, 59, 158).
Aa
White text reads best on this color (9.33:1).
About this color
#313B9E is a dark, vivid blue. In OKLCH its lightness is 41%, its chroma 0.159 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.029 away. White text reads best on it, at 9.33:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | vivid (0.159) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.24:1 |
| White text | 9.33:1 |
Values
| HEX | #313B9E |
| RGB | rgb(49, 59, 158) |
| HSL | hsl(234, 53%, 41%) |
| OKLCH | oklch(40.9% 0.159 272.7) |
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 #313B9E | 9.33:1 | AAA | Lc -95.4 | Preferred for body text |
| Black text on #313B9E | 2.24:1 | Fails | Lc 12.9 | Not readable |
| #313B9E text on white | 9.33:1 | AAA | Lc 91.0 | Preferred for body text |
| #313B9E text on black | 2.24:1 | Fails | Lc -11.3 | 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 800.
-
Step 50
50
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FD
oklch(93.5% 0.028 272.5)
-
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
#8298FD
oklch(70.7% 0.15 272.8)
-
Step 500
500
#667BFA
oklch(63.2% 0.189 272.8)
-
Step 600
600
#505FE9
oklch(55.5% 0.207 272.9)
-
Step 700
700
#414ECB
oklch(49.2% 0.192 272.6)
-
Step 800
800 (this color)
#313B9E
oklch(40.9% 0.159 272.7)
-
Step 900
900
#2D3882
oklch(37.6% 0.124 272.6)
-
Step 950
950
#1A224C
oklch(27.1% 0.078 272.1)
#313B9E 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) | #004CA1 | 0.049 |
| Deuteranopia (no green cones) | #00429C | 0.038 |
| Tritanopia (no blue cones) | #005467 | 0.128 |
| Achromatopsia (no color) | #474747 | 0.159 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313B9E
#313B9E
oklch(40.9% 0.159 272.7)
- #5A4800
#5A4800
oklch(40.9% 0.084 92.4)
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 #313B9E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.029
- Blueberry #464196 ΔE 0.039
- Cobalt #1E488F ΔE 0.045
- Dark Slate Blue #483D8B ΔE 0.048
- Indigo Blue #3A18B1 ΔE 0.064
- Blue Blue #2242C7 ΔE 0.069
- Majorelle Blue #3F37C9 ΔE 0.072
- Dusk Blue #26538D ΔE 0.072
Use #313B9E 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.