Color

#173c87

#173c87
hex#173c87
rgbrgb(23, 60, 135)
hslhsl(220, 71%, 31%)
oklchoklch(0.378 0.133 262.3)
Closest name: Deep Space Royal (#223382)Relative luminance 0.0516

Colors that go with #173c87

Charcoal, Steel Blue and Blue lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#876217

#177487 · #2a1787

#87173c · #3c8717

Split-complementary

Open in tool →

#872a17 · #748717

#871774 · #876217 · #17872a

Contrast

#173c87 as textRatioAAAA largeAAAFix
Aaon white
10.33:1passpasspassPasses AAA — no fix needed.
Aaon black
2.03:1failfailfail
  • AA: use #3b71de as the text (4.6:1)
  • AAA: use #6b94e6 as the text (7:1)
  • AA: or shift the background to #adadad (4.6:1)
  • AAA: or shift the background to #d6d6d6 (7.11:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #173c87 as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#173c87 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #173c87
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #173c87 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/173c87-9ca5c4-df694e-211f2d-e9f0f1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md