#21559E
Closest named color: Dusk Blue (#26538D). oklch(45.6% 0.131 257.7), rgb(33, 85, 158).
Aa
White text reads best on this color (7.34:1).
About this color
#21559E is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.131 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.027 away. White text reads best on it, at 7.34:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.85:1 |
| White text | 7.34:1 |
Values
| HEX | #21559E |
| RGB | rgb(33, 85, 158) |
| HSL | hsl(215, 65%, 37%) |
| OKLCH | oklch(45.6% 0.131 257.7) |
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 #21559E | 7.34:1 | AAA | Lc -90.0 | Preferred for body text |
| Black text on #21559E | 2.85:1 | Fails | Lc 18.9 | Dividers and decoration only |
| #21559E text on white | 7.34:1 | AAA | Lc 85.1 | Fine for body text |
| #21559E text on black | 2.85:1 | Fails | Lc -16.9 | Dividers and decoration only |
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 800.
-
Step 50
50
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E1EBF9
oklch(93.7% 0.022 256.7)
-
Step 200
200
#C8DBF6
oklch(88.6% 0.043 257.1)
-
Step 300
300
#A2C3F2
oklch(81% 0.076 257.2)
-
Step 400
400
#6FA2EC
oklch(70.7% 0.122 257.6)
-
Step 500
500
#4788E6
oklch(63% 0.157 257.8)
-
Step 600
600
#2770D4
oklch(55.6% 0.17 257.6)
-
Step 700
700
#1A5DB8
oklch(49.1% 0.158 257.8)
-
Step 800
800 (this color)
#21559E
oklch(45.6% 0.131 257.7)
-
Step 900
900
#1B4177
oklch(37.9% 0.102 257.7)
-
Step 950
950
#112645
oklch(27% 0.064 258.1)
#21559E 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) | #2F5CA1 | 0.025 |
| Deuteranopia (no green cones) | #11519D | 0.016 |
| Tritanopia (no blue cones) | #006672 | 0.099 |
| Achromatopsia (no color) | #565656 | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21559E
#21559E
oklch(45.6% 0.131 257.7)
- #744F00
#744F00
oklch(45.7% 0.095 77.7)
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 #21559E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.027
- Denim Blue #3B5B92 ΔE 0.038
- Cobalt #1E488F ΔE 0.042
- Light Navy Blue #2E5A88 ΔE 0.043
- Light Navy #155084 ΔE 0.045
- Deep Sea Blue #015482 ΔE 0.050
- Dusky Blue #475F94 ΔE 0.055
- Twilight #4E518B ΔE 0.057
Use #21559E 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.