#313F75
Closest named color: Twilight Blue (#0A437A). oklch(38.4% 0.093 270.6), rgb(49, 63, 117).
Aa
White text reads best on this color (10.00:1).
About this color
#313F75 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.093 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.035 away. White text reads best on it, at 10.00:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.093) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.09:1 |
| White text | 10.00:1 |
Values
| HEX | #313F75 |
| RGB | rgb(49, 63, 117) |
| HSL | hsl(228, 41%, 33%) |
| OKLCH | oklch(38.4% 0.093 270.6) |
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 #313F75 | 10.00:1 | AAA | Lc -97.2 | Preferred for body text |
| Black text on #313F75 | 2.09:1 | Fails | Lc 10.9 | Not readable |
| #313F75 text on white | 10.00:1 | AAA | Lc 93.1 | Preferred for body text |
| #313F75 text on black | 2.09:1 | Fails | Lc -9.4 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E4EAF8
oklch(93.7% 0.02 267.3)
-
Step 200
200
#CFD8F4
oklch(88.4% 0.04 271.4)
-
Step 300
300
#AFBFEF
oklch(80.9% 0.07 270.4)
-
Step 400
400
#869CE7
oklch(70.6% 0.113 270.8)
-
Step 500
500
#6982E0
oklch(63.1% 0.144 270.6)
-
Step 600
600
#526ACD
oklch(55.6% 0.155 270.4)
-
Step 700
700
#4357B2
oklch(49% 0.146 270.8)
-
Step 800
800
#374890
oklch(42.7% 0.12 270.6)
-
Step 900
900 (this color)
#313F75
oklch(38.4% 0.093 270.6)
-
Step 950
950
#1C2443
oklch(27% 0.059 271.1)
#313F75 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) | #274577 | 0.019 |
| Deuteranopia (no green cones) | #1F3F74 | 0.022 |
| Tritanopia (no blue cones) | #0A4B54 | 0.084 |
| Achromatopsia (no color) | #424242 | 0.094 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #313F75
#313F75
oklch(38.4% 0.093 270.6)
- #534100
#534100
oklch(38.4% 0.078 90.9)
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 #313F75, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.035
- Cobalt #1E488F ΔE 0.049
- Dark Slate Blue #483D8B ΔE 0.052
- Light Navy #155084 ΔE 0.053
- Marine Blue #01386A ΔE 0.055
- Dark Grey Blue #29465B ΔE 0.056
- Dusk Blue #26538D ΔE 0.064
- Blueberry #464196 ΔE 0.064
Use #313F75 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.