#1B1C39
Closest named color: Oxford Blue (#1B263B). oklch(24.2% 0.055 280), rgb(27, 28, 57).
Aa
White text reads best on this color (16.51:1).
About this color
#1B1C39 is a very dark, muted blue. In OKLCH its lightness is 24%, its chroma 0.055 and its hue 280°. Its hue sits on the cool side of the wheel. The nearest named color is Oxford Blue (#1B263B), ΔE 0.033 away. White text reads best on it, at 16.51:1.
| Hue family | Blues |
| Lightness | very dark (24%) |
| Chroma | muted (0.055) |
| Temperature | cool |
| Nearest name | Oxford Blue (#1B263B) |
| Black text | 1.27:1 |
| White text | 16.51:1 |
Values
| HEX | #1B1C39 |
| RGB | rgb(27, 28, 57) |
| HSL | hsl(238, 36%, 16%) |
| OKLCH | oklch(24.2% 0.055 280) |
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 #1B1C39 | 16.51:1 | AAA | Lc -105.9 | Preferred for body text |
| Black text on #1B1C39 | 1.27:1 | Fails | Lc 0.0 | Not readable |
| #1B1C39 text on white | 16.51:1 | AAA | Lc 103.4 | Preferred for body text |
| #1B1C39 text on black | 1.27:1 | 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
#F4F5FB
oklch(97.1% 0.008 278.6)
-
Step 100
100
#E7E9F7
oklch(93.7% 0.019 279.5)
-
Step 200
200
#D4D7F1
oklch(88.5% 0.036 280.4)
-
Step 300
300
#B8BDEA
oklch(81% 0.064 279.9)
-
Step 400
400
#9499E0
oklch(70.7% 0.104 280.3)
-
Step 500
500
#7B7FD7
oklch(63.2% 0.131 280)
-
Step 600
600
#6566C5
oklch(55.6% 0.144 280.2)
-
Step 700
700
#5454AA
oklch(49% 0.134 280.2)
-
Step 800
800
#44458A
oklch(42.6% 0.112 279.9)
-
Step 900
900
#393B6E
oklch(37.7% 0.086 279.7)
-
Step 950
950 (this color)
#1B1C39
oklch(24.2% 0.055 280)
#1B1C39 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) | #11203A | 0.018 |
| Deuteranopia (no green cones) | #0F1E38 | 0.019 |
| Tritanopia (no blue cones) | #112227 | 0.048 |
| Achromatopsia (no color) | #1F1F1F | 0.055 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B1C39
#1B1C39
oklch(24.2% 0.055 280)
- #252000
#252000
oklch(24.2% 0.05 100.9)
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 #1B1C39, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Oxford Blue #1B263B ΔE 0.033
- Dark #1B2431 ΔE 0.035
- Rich Black #0D1B2A ΔE 0.038
- Jet #212529 ΔE 0.051
- Navy Blue #001146 ΔE 0.061
- Space Cadet #2B2D42 ΔE 0.065
- Dark Indigo #1F0954 ΔE 0.068
- Midnight Purple #280137 ΔE 0.071
Use #1B1C39 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.