Color

#131b71

#131b71
hex#131b71
rgbrgb(19, 27, 113)
hslhsl(235, 71%, 26%)
oklchoklch(0.289 0.144 269.5)
Closest name: midnightblue (#191970)Relative luminance 0.0211

Colors that go with #131b71

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 →

#716a13

#134a71 · #3a1371

#71131b · #1b7113

Split-complementary

Open in tool →

#713a13 · #4a7113

#71134a · #716a13 · #13713a

Contrast

#131b71 as textRatioAAAA largeAAAFix
Aaon white
14.76:1passpasspassPasses AAA — no fix needed.
Aaon black
1.42:1failfailfail
  • AA: use #5e69e4 as the text (4.62:1)
  • AAA: use #8991eb as the text (7.31:1)
  • AA: or shift the background to #8f8f8f (4.56:1)
  • AAA: or shift the background to #b3b3b3 (7.04:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #131b71 as the background.

Brands using this color

Fonts for this mood

#131b71 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #131b71
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 #131b71 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/131b71-9e9cc4-df8d4e-241f2d-e9eef1?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