#10203B
Closest named color: Oxford Blue (#1B263B). oklch(24.5% 0.056 260.3), rgb(16, 32, 59).
Aa
White text reads best on this color (16.25:1).
About this color
#10203B is a very dark, muted blue. In OKLCH its lightness is 25%, its chroma 0.056 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Oxford Blue (#1B263B), ΔE 0.027 away. White text reads best on it, at 16.25:1.
| Hue family | Blues |
| Lightness | very dark (25%) |
| Chroma | muted (0.056) |
| Temperature | cool |
| Nearest name | Oxford Blue (#1B263B) |
| Black text | 1.29:1 |
| White text | 16.25:1 |
Values
| HEX | #10203B |
| RGB | rgb(16, 32, 59) |
| HSL | hsl(218, 57%, 15%) |
| OKLCH | oklch(24.5% 0.056 260.3) |
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 #10203B | 16.25:1 | AAA | Lc -105.6 | Preferred for body text |
| Black text on #10203B | 1.29:1 | Fails | Lc 0.0 | Not readable |
| #10203B text on white | 16.25:1 | AAA | Lc 103.1 | Preferred for body text |
| #10203B text on black | 1.29:1 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E3EAF7
oklch(93.6% 0.019 263)
-
Step 200
200
#CBDAF2
oklch(88.5% 0.037 259.8)
-
Step 300
300
#A8C2EC
oklch(80.9% 0.066 259.9)
-
Step 400
400
#7AA1E3
oklch(70.7% 0.106 260.6)
-
Step 500
500
#5788DB
oklch(63% 0.136 260.4)
-
Step 600
600
#3C70C8
oklch(55.5% 0.148 260.2)
-
Step 700
700
#2F5EAD
oklch(49.2% 0.136 260.1)
-
Step 800
800
#274D8C
oklch(42.7% 0.113 259.9)
-
Step 900
900
#244170
oklch(37.8% 0.088 259.6)
-
Step 950
950 (this color)
#10203B
oklch(24.5% 0.056 260.3)
#10203B 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) | #14223C | 0.009 |
| Deuteranopia (no green cones) | #0E1E3A | 0.008 |
| Tritanopia (no blue cones) | #00262A | 0.047 |
| Achromatopsia (no color) | #202020 | 0.056 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #10203B
#10203B
oklch(24.5% 0.056 260.3)
- #2D1D00
#2D1D00
oklch(24.5% 0.051 79.5)
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 #10203B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Oxford Blue #1B263B ΔE 0.027
- Dark #1B2431 ΔE 0.031
- Rich Black #0D1B2A ΔE 0.035
- Jet #212529 ΔE 0.050
- Navy Blue #001146 ΔE 0.058
- Space Cadet #2B2D42 ΔE 0.064
- Gunmetal #293241 ΔE 0.075
- Marine #042E60 ΔE 0.075
Use #10203B 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.