#21566E
Closest named color: Petrol (#005F6A). oklch(42.9% 0.068 231), rgb(33, 86, 110).
Aa
White text reads best on this color (8.01:1).
About this color
#21566E is a dark, muted blue. In OKLCH its lightness is 43%, its chroma 0.068 and its hue 231°. Its hue sits on the cool side of the wheel. The nearest named color is Petrol (#005F6A), ΔE 0.033 away. White text reads best on it, at 8.01:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | muted (0.068) |
| Temperature | cool |
| Nearest name | Petrol (#005F6A) |
| Black text | 2.62:1 |
| White text | 8.01:1 |
Values
| HEX | #21566E |
| RGB | rgb(33, 86, 110) |
| HSL | hsl(199, 54%, 28%) |
| OKLCH | oklch(42.9% 0.068 231) |
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 #21566E | 8.01:1 | AAA | Lc -92.2 | Preferred for body text |
| Black text on #21566E | 2.62:1 | Fails | Lc 16.5 | Dividers and decoration only |
| #21566E text on white | 8.01:1 | AAA | Lc 87.5 | Fine for body text |
| #21566E text on black | 2.62:1 | Fails | Lc -14.6 | 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 800.
-
Step 50
50
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3EBF0
oklch(93.5% 0.011 234.8)
-
Step 200
200
#CBDCE5
oklch(88.4% 0.022 230.6)
-
Step 300
300
#A8C6D6
oklch(81% 0.039 231.2)
-
Step 400
400
#77A8C1
oklch(70.6% 0.064 231)
-
Step 500
500
#5293B2
oklch(63.2% 0.081 230.6)
-
Step 600
600
#337C9E
oklch(55.5% 0.089 231.7)
-
Step 700
700
#246987
oklch(49.2% 0.083 230.7)
-
Step 800
800 (this color)
#21566E
oklch(42.9% 0.068 231)
-
Step 900
900
#214759
oklch(37.8% 0.053 231)
-
Step 950
950
#142934
oklch(26.9% 0.034 232.8)
#21566E 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) | #4A556F | 0.047 |
| Deuteranopia (no green cones) | #3F4D6E | 0.040 |
| Tritanopia (no blue cones) | #005D5E | 0.043 |
| Achromatopsia (no color) | #505050 | 0.068 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21566E
#21566E
oklch(42.9% 0.068 231)
- #6D442B
#6D442B
oklch(42.8% 0.068 51.4)
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 #21566E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Petrol #005F6A ΔE 0.033
- Deep Sea Blue #015482 ΔE 0.038
- Deep Teal #00555A ΔE 0.040
- YInMn Blue #415A77 ΔE 0.041
- Light Navy Blue #2E5A88 ΔE 0.046
- Light Navy #155084 ΔE 0.046
- Dark Slate Gray #2F4F4F ΔE 0.050
- Dark Grey Blue #29465B ΔE 0.052
Use #21566E 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.