#121B3B
Closest named color: Rich Black (#0D1B2A). oklch(23.4% 0.063 269.3), rgb(18, 27, 59).
Aa
White text reads best on this color (16.85:1).
About this color
#121B3B is a very dark, muted blue. In OKLCH its lightness is 23%, its chroma 0.063 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Rich Black (#0D1B2A), ΔE 0.035 away. White text reads best on it, at 16.85:1.
| Hue family | Blues |
| Lightness | very dark (23%) |
| Chroma | muted (0.063) |
| Temperature | cool |
| Nearest name | Rich Black (#0D1B2A) |
| Black text | 1.24:1 |
| White text | 16.85:1 |
Values
| HEX | #121B3B |
| RGB | rgb(18, 27, 59) |
| HSL | hsl(227, 53%, 15%) |
| OKLCH | oklch(23.4% 0.063 269.3) |
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 #121B3B | 16.85:1 | AAA | Lc -106.1 | Preferred for body text |
| Black text on #121B3B | 1.24:1 | Fails | Lc 0.0 | Not readable |
| #121B3B text on white | 16.85:1 | AAA | Lc 103.7 | Preferred for body text |
| #121B3B text on black | 1.24:1 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E4EAF9
oklch(93.7% 0.021 268.4)
-
Step 200
200
#CED9F5
oklch(88.6% 0.04 268.5)
-
Step 300
300
#ADBFF2
oklch(80.9% 0.075 269.5)
-
Step 400
400
#839DEB
oklch(70.8% 0.118 269.2)
-
Step 500
500
#6582E5
oklch(63.1% 0.152 269.4)
-
Step 600
600
#4D69D3
oklch(55.6% 0.166 269.3)
-
Step 700
700
#3F57B6
oklch(49.1% 0.153 269.4)
-
Step 800
800
#344894
oklch(42.8% 0.127 269.3)
-
Step 900
900
#2D3D76
oklch(37.8% 0.099 269.4)
-
Step 950
950 (this color)
#121B3B
oklch(23.4% 0.063 269.3)
#121B3B 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) | #0B1F3C | 0.014 |
| Deuteranopia (no green cones) | #061B3A | 0.015 |
| Tritanopia (no blue cones) | #002228 | 0.053 |
| Achromatopsia (no color) | #1D1D1D | 0.063 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #121B3B
#121B3B
oklch(23.4% 0.063 269.3)
- #271C00
#271C00
oklch(23.3% 0.048 88.1)
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 #121B3B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Rich Black #0D1B2A ΔE 0.035
- Oxford Blue #1B263B ΔE 0.041
- Dark #1B2431 ΔE 0.043
- Navy Blue #001146 ΔE 0.047
- Jet #212529 ΔE 0.061
- Dark Indigo #1F0954 ΔE 0.064
- Night Blue #040348 ΔE 0.071
- Midnight Purple #280137 ΔE 0.076
Use #121B3B 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.