#173A4E
Closest named color: Dark Blue Grey (#1F3B4D). oklch(33.3% 0.054 236.6), rgb(23, 58, 78).
Aa
White text reads best on this color (11.98:1).
About this color
#173A4E is a dark, muted blue. In OKLCH its lightness is 33%, its chroma 0.054 and its hue 237°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.009 away. White text reads best on it, at 11.98:1.
| Hue family | Blues |
| Lightness | dark (33%) |
| Chroma | muted (0.054) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.75:1 |
| White text | 11.98:1 |
Values
| HEX | #173A4E |
| RGB | rgb(23, 58, 78) |
| HSL | hsl(202, 54%, 20%) |
| OKLCH | oklch(33.3% 0.054 236.6) |
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 #173A4E | 11.98:1 | AAA | Lc -100.8 | Preferred for body text |
| Black text on #173A4E | 1.75:1 | Fails | Lc 0.0 | Not readable |
| #173A4E text on white | 11.98:1 | AAA | Lc 97.3 | Preferred for body text |
| #173A4E text on black | 1.75:1 | 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 900.
-
Step 50
50
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF1
oklch(93.6% 0.012 239.9)
-
Step 200
200
#CCDCE6
oklch(88.5% 0.022 235)
-
Step 300
300
#A9C5D8
oklch(80.9% 0.041 237.7)
-
Step 400
400
#7AA7C4
oklch(70.7% 0.064 237.1)
-
Step 500
500
#5691B5
oklch(63.1% 0.082 236.9)
-
Step 600
600
#397BA1
oklch(55.7% 0.089 236.7)
-
Step 700
700
#2A678A
oklch(49% 0.084 237.2)
-
Step 800
800
#255470
oklch(42.6% 0.069 237.6)
-
Step 900
900 (this color)
#173A4E
oklch(33.3% 0.054 236.6)
-
Step 950
950
#152935
oklch(27% 0.034 236.3)
#173A4E 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) | #313A4F | 0.033 |
| Deuteranopia (no green cones) | #29344E | 0.027 |
| Tritanopia (no blue cones) | #003F41 | 0.036 |
| Achromatopsia (no color) | #373737 | 0.054 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173A4E
#173A4E
oklch(33.3% 0.054 236.6)
- #4B2E19
#4B2E19
oklch(33.2% 0.054 55.5)
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 #173A4E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.009
- Midnight Green #073B4C ΔE 0.012
- Prussian Blue #1D3557 ΔE 0.026
- Gunmetal #293241 ΔE 0.034
- Onyx #343A40 ΔE 0.043
- Charcoal #264653 ΔE 0.045
- Space Cadet #2B2D42 ΔE 0.046
- Dark Grey Blue #29465B ΔE 0.049
Use #173A4E 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.