#172839
Closest named color: Oxford Blue (#1B263B). oklch(27.1% 0.039 249.5), rgb(23, 40, 57).
Aa
White text reads best on this color (15.01:1).
About this color
#172839 is a dark, muted blue. In OKLCH its lightness is 27%, its chroma 0.039 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Oxford Blue (#1B263B), ΔE 0.010 away. White text reads best on it, at 15.01:1.
| Hue family | Blues |
| Lightness | dark (27%) |
| Chroma | muted (0.039) |
| Temperature | cool |
| Nearest name | Oxford Blue (#1B263B) |
| Black text | 1.39:1 |
| White text | 15.01:1 |
Values
| HEX | #172839 |
| RGB | rgb(23, 40, 57) |
| HSL | hsl(210, 43%, 16%) |
| OKLCH | oklch(27.1% 0.039 249.5) |
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 #172839 | 15.01:1 | AAA | Lc -104.6 | Preferred for body text |
| Black text on #172839 | 1.39:1 | Fails | Lc 0.0 | Not readable |
| #172839 text on white | 15.01:1 | AAA | Lc 101.8 | Preferred for body text |
| #172839 text on black | 1.39:1 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E3EBF3
oklch(93.6% 0.014 248)
-
Step 200
200
#CDDBEA
oklch(88.5% 0.026 250)
-
Step 300
300
#AAC4DE
oklch(80.9% 0.046 248.4)
-
Step 400
400
#7DA5CD
oklch(70.8% 0.073 248.9)
-
Step 500
500
#5B8EC1
oklch(63.2% 0.095 249.5)
-
Step 600
600
#3F77AD
oklch(55.6% 0.103 249.4)
-
Step 700
700
#316495
oklch(49.1% 0.096 249.6)
-
Step 800
800
#295279
oklch(42.8% 0.08 249.1)
-
Step 900
900
#264461
oklch(37.7% 0.062 249)
-
Step 950
950 (this color)
#172839
oklch(27.1% 0.039 249.5)
#172839 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) | #21293A | 0.016 |
| Deuteranopia (no green cones) | #1D2539 | 0.013 |
| Tritanopia (no blue cones) | #062C2E | 0.034 |
| Achromatopsia (no color) | #272727 | 0.039 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #172839
#172839
oklch(27.1% 0.039 249.5)
- #332310
#332310
oklch(27.1% 0.039 69.6)
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 #172839, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Oxford Blue #1B263B ΔE 0.010
- Dark #1B2431 ΔE 0.018
- Jet #212529 ΔE 0.031
- Space Cadet #2B2D42 ΔE 0.040
- Gunmetal #293241 ΔE 0.046
- Rich Black #0D1B2A ΔE 0.053
- Prussian Blue #1D3557 ΔE 0.064
- Midnight Green #073B4C ΔE 0.065
Use #172839 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.