#173D4E
Closest named color: Dark Blue Grey (#1F3B4D). oklch(34.1% 0.052 230.3), rgb(23, 61, 78).
Aa
White text reads best on this color (11.57:1).
About this color
#173D4E is a dark, muted blue. In OKLCH its lightness is 34%, its chroma 0.052 and its hue 230°. 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 11.57:1.
| Hue family | Blues |
| Lightness | dark (34%) |
| Chroma | muted (0.052) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.81:1 |
| White text | 11.57:1 |
Values
| HEX | #173D4E |
| RGB | rgb(23, 61, 78) |
| HSL | hsl(199, 54%, 20%) |
| OKLCH | oklch(34.1% 0.052 230.3) |
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 #173D4E | 11.57:1 | AAA | Lc -100.2 | Preferred for body text |
| Black text on #173D4E | 1.81:1 | Fails | Lc 7.4 | Not readable |
| #173D4E text on white | 11.57:1 | AAA | Lc 96.5 | Preferred for body text |
| #173D4E text on black | 1.81:1 | 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
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3EBF0
oklch(93.5% 0.011 234.8)
-
Step 200
200
#CBDCE5
oklch(88.4% 0.022 230.6)
-
Step 300
300
#A8C6D5
oklch(80.9% 0.039 229.5)
-
Step 400
400
#78A8C0
oklch(70.6% 0.062 230.4)
-
Step 500
500
#5393B1
oklch(63.2% 0.08 230.1)
-
Step 600
600
#347C9C
oklch(55.5% 0.087 230.4)
-
Step 700
700
#266986
oklch(49.2% 0.081 230.3)
-
Step 800
800
#21566D
oklch(42.8% 0.067 229.9)
-
Step 900
900 (this color)
#173D4E
oklch(34.1% 0.052 230.3)
-
Step 950
950
#142934
oklch(26.9% 0.034 232.8)
#173D4E 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) | #343C4F | 0.036 |
| Deuteranopia (no green cones) | #2D364E | 0.033 |
| Tritanopia (no blue cones) | #004243 | 0.033 |
| Achromatopsia (no color) | #393939 | 0.052 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173D4E
#173D4E
oklch(34.1% 0.052 230.3)
- #4E301F
#4E301F
oklch(34.1% 0.052 49.9)
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 #173D4E, 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 0.014
- Prussian Blue #1D3557 ΔE 0.035
- Charcoal #264653 ΔE 0.036
- Gunmetal #293241 ΔE 0.040
- Onyx #343A40 ΔE 0.040
- Dark Grey Blue #29465B ΔE 0.041
- Space Cadet #2B2D42 ΔE 0.054
Use #173D4E 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.