#2F378A
Closest named color: Dark Slate Blue (#483D8B). oklch(38.2% 0.137 273.8), rgb(47, 55, 138).
Aa
White text reads best on this color (10.32:1).
About this color
#2F378A is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.137 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Blue (#483D8B), ΔE 0.044 away. White text reads best on it, at 10.32:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.137) |
| Temperature | cool |
| Nearest name | Dark Slate Blue (#483D8B) |
| Black text | 2.03:1 |
| White text | 10.32:1 |
Values
| HEX | #2F378A |
| RGB | rgb(47, 55, 138) |
| HSL | hsl(235, 49%, 36%) |
| OKLCH | oklch(38.2% 0.137 273.8) |
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 #2F378A | 10.32:1 | AAA | Lc -97.6 | Preferred for body text |
| Black text on #2F378A | 2.03:1 | Fails | Lc 10.4 | Not readable |
| #2F378A text on white | 10.32:1 | AAA | Lc 93.6 | Preferred for body text |
| #2F378A text on black | 2.03:1 | Fails | Lc -8.9 | 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
#CDD7FF
oklch(88.4% 0.056 274.2)
-
Step 300
300
#ADBDFF
oklch(81% 0.095 273.6)
-
Step 400
400
#8397FF
oklch(70.7% 0.153 273.6)
-
Step 500
500
#6778FF
oklch(63% 0.199 273.8)
-
Step 600
600
#5159F5
oklch(55.5% 0.229 273.9)
-
Step 700
700
#4348D5
oklch(49.1% 0.211 273.9)
-
Step 800
800
#363CAC
oklch(42.6% 0.175 273.8)
-
Step 900
900 (this color)
#2F378A
oklch(38.2% 0.137 273.8)
-
Step 950
950
#1A2050
oklch(26.9% 0.087 273.6)
#2F378A 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) | #00448D | 0.044 |
| Deuteranopia (no green cones) | #003C88 | 0.039 |
| Tritanopia (no blue cones) | #004B5B | 0.113 |
| Achromatopsia (no color) | #404040 | 0.137 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2F378A
#2F378A
oklch(38.2% 0.137 273.8)
- #514200
#514200
oklch(38.4% 0.079 94.3)
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 #2F378A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Blue #483D8B ΔE 0.044
- Cobalt #1E488F ΔE 0.046
- Blueberry #464196 ΔE 0.050
- Twilight Blue #0A437A ΔE 0.053
- Sapphire #2138AB ΔE 0.056
- Marine Blue #01386A ΔE 0.071
- Light Navy #155084 ΔE 0.072
- Dusk Blue #26538D ΔE 0.076
Use #2F378A 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.