Color

#231b7e

#231b7e
hex#231b7e
rgbrgb(35, 27, 126)
hslhsl(245, 65%, 30%)
oklchoklch(0.314 0.157 275.9)
Closest name: midnightblue (#191970)Relative luminance 0.0265

Colors that go with #231b7e

Steel Blue, Charcoal and Cobalt 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 →

#767e1b

#1b447e · #551b7e

#7e231b · #1b7e23

Split-complementary

Open in tool →

#7e551b · #447e1b

#7e1b44 · #767e1b · #1b7e55

Contrast

#231b7e as textRatioAAAA largeAAAFix
Aaon white
13.73:1passpasspassPasses AAA — no fix needed.
Aaon black
1.53:1failfailfail
  • AA: use #6e63de as the text (4.5:1)
  • AAA: use #958de7 as the text (7.24:1)
  • AA: or shift the background to #949494 (4.53:1)
  • AAA: or shift the background to #bababa (7.07:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #231b7e as the background.

Brands using this color

Fonts for this mood

#231b7e reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #231b7e
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 #231b7e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/231b7e-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