#21355D
Closest named color: Prussian Blue (#1D3557). oklch(33.4% 0.075 262.9), rgb(33, 53, 93).
Aa
White text reads best on this color (12.12:1).
About this color
#21355D is a dark, moderately saturated blue. In OKLCH its lightness is 33%, its chroma 0.075 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Prussian Blue (#1D3557), ΔE 0.012 away. White text reads best on it, at 12.12:1.
| Hue family | Blues |
| Lightness | dark (33%) |
| Chroma | moderately saturated (0.075) |
| Temperature | cool |
| Nearest name | Prussian Blue (#1D3557) |
| Black text | 1.73:1 |
| White text | 12.12:1 |
Values
| HEX | #21355D |
| RGB | rgb(33, 53, 93) |
| HSL | hsl(220, 48%, 25%) |
| OKLCH | oklch(33.4% 0.075 262.9) |
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 #21355D | 12.12:1 | AAA | Lc -101.1 | Preferred for body text |
| Black text on #21355D | 1.73:1 | Fails | Lc 0.0 | Not readable |
| #21355D text on white | 12.12:1 | AAA | Lc 97.5 | Preferred for body text |
| #21355D text on black | 1.73:1 | Fails | Lc 0.0 | 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
#F3F6FB
oklch(97.2% 0.007 260.7)
-
Step 100
100
#E4EAF5
oklch(93.6% 0.016 262.8)
-
Step 200
200
#CEDAEF
oklch(88.6% 0.032 261.7)
-
Step 300
300
#ADC1E6
oklch(80.8% 0.057 262.7)
-
Step 400
400
#83A1DA
oklch(70.8% 0.09 262.8)
-
Step 500
500
#6488CF
oklch(63.1% 0.115 263)
-
Step 600
600
#4B71BC
oklch(55.6% 0.125 262.7)
-
Step 700
700
#3C5EA3
oklch(49.1% 0.118 263)
-
Step 800
800
#324D84
oklch(42.7% 0.097 263.2)
-
Step 900
900 (this color)
#21355D
oklch(33.4% 0.075 262.9)
-
Step 950
950
#1A263E
oklch(27% 0.048 263.3)
#21355D 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) | #24395F | 0.014 |
| Deuteranopia (no green cones) | #1B335C | 0.010 |
| Tritanopia (no blue cones) | #003E44 | 0.066 |
| Achromatopsia (no color) | #363636 | 0.075 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21355D
#21355D
oklch(33.4% 0.075 262.9)
- #473200
#473200
oklch(33.3% 0.068 82.8)
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 #21355D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Prussian Blue #1D3557 ΔE 0.012
- Marine Blue #01386A ΔE 0.031
- Marine #042E60 ΔE 0.038
- Dark Blue Grey #1F3B4D ΔE 0.039
- Midnight Green #073B4C ΔE 0.046
- Gunmetal #293241 ΔE 0.049
- Space Cadet #2B2D42 ΔE 0.050
- Dark Grey Blue #29465B ΔE 0.058
Use #21355D 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.