#173F53
Closest named color: Dark Blue Grey (#1F3B4D). oklch(34.9% 0.056 233.5), rgb(23, 63, 83).
Aa
White text reads best on this color (11.21:1).
About this color
#173F53 is a dark, muted blue. In OKLCH its lightness is 35%, its chroma 0.056 and its hue 233°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.015 away. White text reads best on it, at 11.21:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | muted (0.056) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.87:1 |
| White text | 11.21:1 |
Values
| HEX | #173F53 |
| RGB | rgb(23, 63, 83) |
| HSL | hsl(200, 57%, 21%) |
| OKLCH | oklch(34.9% 0.056 233.5) |
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 #173F53 | 11.21:1 | AAA | Lc -99.5 | Preferred for body text |
| Black text on #173F53 | 1.87:1 | Fails | Lc 8.2 | Not readable |
| #173F53 text on white | 11.21:1 | AAA | Lc 95.7 | Preferred for body text |
| #173F53 text on black | 1.87:1 | 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
#E2EBF1
oklch(93.5% 0.013 236.6)
-
Step 200
200
#CBDCE6
oklch(88.5% 0.023 233.4)
-
Step 300
300
#A7C6D8
oklch(81% 0.042 233.5)
-
Step 400
400
#76A8C4
oklch(70.6% 0.067 233.5)
-
Step 500
500
#4F92B6
oklch(63% 0.087 234)
-
Step 600
600
#2F7CA2
oklch(55.6% 0.095 233.7)
-
Step 700
700
#21688A
oklch(49% 0.087 233.7)
-
Step 800
800
#1E5570
oklch(42.6% 0.072 233.6)
-
Step 900
900 (this color)
#173F53
oklch(34.9% 0.056 233.5)
-
Step 950
950
#132935
oklch(26.9% 0.036 234.1)
#173F53 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) | #353E54 | 0.036 |
| Deuteranopia (no green cones) | #2D3853 | 0.032 |
| Tritanopia (no blue cones) | #004446 | 0.035 |
| Achromatopsia (no color) | #3B3B3B | 0.057 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #173F53
#173F53
oklch(34.9% 0.056 233.5)
- #51321D
#51321D
oklch(35% 0.056 54)
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 #173F53, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.015
- Midnight Green #073B4C ΔE 0.021
- Charcoal #264653 ΔE 0.030
- Dark Grey Blue #29465B ΔE 0.033
- Prussian Blue #1D3557 ΔE 0.035
- Onyx #343A40 ΔE 0.044
- Gunmetal #293241 ΔE 0.047
- Dark Teal #014D4E ΔE 0.051
Use #173F53 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.