Color

#1d288b

#1d288b
hex#1d288b
rgbrgb(29, 40, 139)
hslhsl(234, 65%, 33%)
oklchoklch(0.345 0.162 269.9)
Closest name: Deepsea Kraken (#082599)Relative luminance 0.0364

Colors that go with #1d288b

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 →

#8b801d

#1d5f8b · #491d8b

#8b1d28 · #288b1d

Split-complementary

Open in tool →

#8b491d · #5f8b1d

#8b1d5f · #8b801d · #1d8b49

Contrast

#1d288b as textRatioAAAA largeAAAFix
Aaon white
12.15:1passpasspassPasses AAA — no fix needed.
Aaon black
1.73:1failfailfail
  • AA: use #5f6cdd as the text (4.68:1)
  • AAA: use #858fe5 as the text (7.06:1)
  • AA: or shift the background to #9e9e9e (4.53:1)
  • AAA: or shift the background to #c7c7c7 (7.19:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1d288b 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

#1d288b reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1d288b
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 #1d288b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1d288b-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