Color

#1b288d

#1b288d
hex#1b288d
rgbrgb(27, 40, 141)
hslhsl(233, 68%, 33%)
oklchoklch(0.346 0.165 269.2)
Closest name: Deepsea Kraken (#082599)Relative luminance 0.0367

Colors that go with #1b288d

Steel Blue, Blue and Charcoal 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 →

#8d801b

#1b628d · #471b8d

#8d1b28 · #288d1b

Split-complementary

Open in tool →

#8d471b · #628d1b

#8d1b62 · #8d801b · #1b8d47

Contrast

#1b288d as textRatioAAAA largeAAAFix
Aaon white
12.11:1passpasspassPasses AAA — no fix needed.
Aaon black
1.73:1failfailfail
  • AA: use #5c6ce0 as the text (4.68:1)
  • AAA: use #8792e8 as the text (7.31:1)
  • AA: or shift the background to #9e9e9e (4.52:1)
  • AAA: or shift the background to #c7c7c7 (7.16:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1b288d as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#1b288d reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1b288d
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 #1b288d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1b288d-9c9cc4-df884e-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