Color

#231c73

#231c73
hex#231c73
rgbrgb(35, 28, 115)
hslhsl(245, 61%, 28%)
oklchoklch(0.303 0.142 277.4)
Closest name: midnightblue (#191970)Relative luminance 0.0243

Colors that go with #231c73

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 →

#6c731c

#1c4073 · #4f1c73

#73231c · #1c7323

Split-complementary

Open in tool →

#734f1c · #40731c

#731c40 · #6c731c · #1c734f

Contrast

#231c73 as textRatioAAAA largeAAAFix
Aaon white
14.14:1passpasspassPasses AAA — no fix needed.
Aaon black
1.49:1failfailfail
  • AA: use #7167da as the text (4.65:1)
  • AAA: use #938ce3 as the text (7.1:1)
  • AA: or shift the background to #949494 (4.66:1)
  • AAA: or shift the background to #b8b8b8 (7.13:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #231c73 as the background.

Brands using this color

Fonts for this mood

#231c73 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #231c73
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 #231c73 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/231c73-a49cc4-dfa54e-261f2d-e9ecf1?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