#21304B
Closest named color: Space Cadet (#2B2D42). oklch(31% 0.053 261.6), rgb(33, 48, 75).
Aa
White text reads best on this color (13.21:1).
About this color
#21304B is a dark, muted blue. In OKLCH its lightness is 31%, its chroma 0.053 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Space Cadet (#2B2D42), ΔE 0.021 away. White text reads best on it, at 13.21:1.
| Hue family | Blues |
| Lightness | dark (31%) |
| Chroma | muted (0.053) |
| Temperature | cool |
| Nearest name | Space Cadet (#2B2D42) |
| Black text | 1.58:1 |
| White text | 13.21:1 |
Values
| HEX | #21304B |
| RGB | rgb(33, 48, 75) |
| HSL | hsl(219, 39%, 21%) |
| OKLCH | oklch(31% 0.053 261.6) |
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 #21304B | 13.21:1 | AAA | Lc -102.7 | Preferred for body text |
| Black text on #21304B | 1.58:1 | Fails | Lc 0.0 | Not readable |
| #21304B text on white | 13.21:1 | AAA | Lc 99.5 | Preferred for body text |
| #21304B text on black | 1.58:1 | 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 950.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF6
oklch(93.5% 0.018 261.3)
-
Step 200
200
#CDDAF1
oklch(88.6% 0.035 262)
-
Step 300
300
#AAC2EA
oklch(81% 0.063 260.6)
-
Step 400
400
#7EA1DF
oklch(70.8% 0.099 261.5)
-
Step 500
500
#5D88D7
oklch(63.1% 0.129 261.7)
-
Step 600
600
#4370C4
oklch(55.5% 0.14 261.7)
-
Step 700
700
#355EA9
oklch(49.2% 0.129 261.4)
-
Step 800
800
#2C4D89
oklch(42.7% 0.107 261.3)
-
Step 900
900
#28406E
oklch(37.6% 0.085 262.3)
-
Step 950
950 (this color)
#21304B
oklch(31% 0.053 261.6)
#21304B 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) | #26324C | 0.010 |
| Deuteranopia (no green cones) | #212E4A | 0.006 |
| Tritanopia (no blue cones) | #0E363A | 0.047 |
| Achromatopsia (no color) | #303030 | 0.053 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21304B
#21304B
oklch(31% 0.053 261.6)
- #3E2D0C
#3E2D0C
oklch(31% 0.053 80.8)
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 #21304B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Space Cadet #2B2D42 ΔE 0.021
- Prussian Blue #1D3557 ΔE 0.024
- Gunmetal #293241 ΔE 0.024
- Dark Blue Grey #1F3B4D ΔE 0.036
- Midnight Green #073B4C ΔE 0.040
- Oxford Blue #1B263B ΔE 0.042
- Marine #042E60 ΔE 0.047
- Onyx #343A40 ΔE 0.054
Use #21304B 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.