#21456C
Closest named color: Twilight Blue (#0A437A). oklch(38.4% 0.079 252.2), rgb(33, 69, 108).
Aa
White text reads best on this color (9.84:1).
About this color
#21456C is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.079 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.030 away. White text reads best on it, at 9.84:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.079) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.13:1 |
| White text | 9.84:1 |
Values
| HEX | #21456C |
| RGB | rgb(33, 69, 108) |
| HSL | hsl(211, 53%, 28%) |
| OKLCH | oklch(38.4% 0.079 252.2) |
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 #21456C | 9.84:1 | AAA | Lc -96.8 | Preferred for body text |
| Black text on #21456C | 2.13:1 | Fails | Lc 11.3 | Not readable |
| #21456C text on white | 9.84:1 | AAA | Lc 92.6 | Preferred for body text |
| #21456C text on black | 2.13:1 | Fails | Lc -9.8 | 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
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E2EBF5
oklch(93.6% 0.017 250.8)
-
Step 200
200
#CADBEF
oklch(88.5% 0.033 252.5)
-
Step 300
300
#A6C4E6
oklch(81% 0.058 251.8)
-
Step 400
400
#75A4DA
oklch(70.6% 0.094 252.5)
-
Step 500
500
#4F8DD0
oklch(63.2% 0.12 251.9)
-
Step 600
600
#3175BD
oklch(55.5% 0.131 252.4)
-
Step 700
700
#2362A3
oklch(49% 0.122 252.3)
-
Step 800
800
#1F5184
oklch(42.8% 0.1 251.7)
-
Step 900
900 (this color)
#21456C
oklch(38.4% 0.079 252.2)
-
Step 950
950
#13283E
oklch(27.1% 0.049 251.1)
#21456C 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) | #34476E | 0.024 |
| Deuteranopia (no green cones) | #29406B | 0.016 |
| Tritanopia (no blue cones) | #004E53 | 0.062 |
| Achromatopsia (no color) | #434343 | 0.079 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21456C
#21456C
oklch(38.4% 0.079 252.2)
- #5D3B05
#5D3B05
oklch(38.3% 0.079 71.6)
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 #21456C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.030
- Dark Grey Blue #29465B ΔE 0.031
- Charcoal #264653 ΔE 0.045
- Light Navy #155084 ΔE 0.047
- Marine Blue #01386A ΔE 0.050
- Deep Sea Blue #015482 ΔE 0.052
- Dark Blue Grey #1F3B4D ΔE 0.057
- Prussian Blue #1D3557 ΔE 0.058
Use #21456C 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.