Color

#1b236f

#1b236f
hex#1b236f
rgbrgb(27, 35, 111)
hslhsl(234, 61%, 27%)
oklchoklch(0.306 0.13 271.5)
Closest name: midnightblue (#191970)Relative luminance 0.0258

Colors that go with #1b236f

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 →

#6f661b

#1b4d6f · #3c1b6f

#6f1b23 · #236f1b

Split-complementary

Open in tool →

#6f3c1b · #4d6f1b

#6f1b4d · #6f661b · #1b6f3c

Contrast

#1b236f as textRatioAAAA largeAAAFix
Aaon white
13.85:1passpasspassPasses AAA — no fix needed.
Aaon black
1.52:1failfailfail
  • AA: use #5f6bd8 as the text (4.58:1)
  • AAA: use #8891e2 as the text (7.2:1)
  • AA: or shift the background to #949494 (4.56:1)
  • AAA: or shift the background to #bababa (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 #1b236f as the background.

Brands using this color

Fonts for this mood

#1b236f reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1b236f
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 #1b236f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1b236f-9d9cc4-df8a4e-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