#373A64
Closest named color: Dark Grey Blue (#29465B). oklch(36.6% 0.072 279.1), rgb(55, 58, 100).
Aa
White text reads best on this color (10.75:1).
About this color
#373A64 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.072 and its hue 279°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.047 away. White text reads best on it, at 10.75:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.072) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 1.95:1 |
| White text | 10.75:1 |
Values
| HEX | #373A64 |
| RGB | rgb(55, 58, 100) |
| HSL | hsl(236, 29%, 30%) |
| OKLCH | oklch(36.6% 0.072 279.1) |
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 #373A64 | 10.75:1 | AAA | Lc -98.8 | Preferred for body text |
| Black text on #373A64 | 1.95:1 | Fails | Lc 9.0 | Not readable |
| #373A64 text on white | 10.75:1 | AAA | Lc 94.9 | Preferred for body text |
| #373A64 text on black | 1.95:1 | Fails | Lc -7.8 | 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
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E7E9F4
oklch(93.6% 0.015 277.8)
-
Step 200
200
#D4D8ED
oklch(88.6% 0.029 277.2)
-
Step 300
300
#B9BEE4
oklch(81% 0.054 279.2)
-
Step 400
400
#959BD6
oklch(70.7% 0.086 279.4)
-
Step 500
500
#7B82CB
oklch(63.1% 0.11 278.6)
-
Step 600
600
#656AB8
oklch(55.6% 0.12 279)
-
Step 700
700
#54589E
oklch(49.1% 0.111 279)
-
Step 800
800
#454880
oklch(42.7% 0.092 279.4)
-
Step 900
900 (this color)
#373A64
oklch(36.6% 0.072 279.1)
-
Step 950
950
#22243C
oklch(27.1% 0.045 279.3)
#373A64 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) | #2B3F66 | 0.021 |
| Deuteranopia (no green cones) | #283C63 | 0.022 |
| Tritanopia (no blue cones) | #29424A | 0.062 |
| Achromatopsia (no color) | #3E3E3E | 0.072 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373A64
#373A64
oklch(36.6% 0.072 279.1)
- #483F06
#483F06
oklch(36.6% 0.072 99.5)
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 #373A64, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.047
- Prussian Blue #1D3557 ΔE 0.047
- Dark Blue Grey #1F3B4D ΔE 0.055
- Twilight Blue #0A437A ΔE 0.056
- Marine Blue #01386A ΔE 0.056
- Charcoal #264653 ΔE 0.058
- Onyx #343A40 ΔE 0.065
- Gunmetal #293241 ΔE 0.068
Use #373A64 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.