Color

#1d4ddd

#1d4ddd
hex#1d4ddd
rgbrgb(29, 77, 221)
hslhsl(225, 77%, 49%)
oklchoklch(0.491 0.224 264.6)
Closest name: C64 Blue (#003aff)Relative luminance 0.1079

Colors that go with #1d4ddd

Charcoal, Sea Green and Amber 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.

Real palettes that use #1d4ddd

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#ddad1d

#1daddd · #4d1ddd

#dd1d4d · #4ddd1d

Split-complementary

Open in tool →

#dd4d1d · #addd1d

#dd1dad · #ddad1d · #1ddd4d

Contrast

#1d4ddd as textRatioAAAA largeAAAFix
Aaon white
6.65:1passpassfail
  • AAA: use #1c4ad4 as the text (7.05:1)
Aaon black
3.16:1failpassfail
  • AA: use #466ee7 as the text (4.64:1)
  • AAA: use #7392ed as the text (7.06:1)
  • AA: or shift the background to #d6d6d6 (4.58:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1d4ddd as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#1d4ddd reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1d4ddd
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 #1d4ddd and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1d4ddd-9ca1c4-df754e-221f2d-e9eff1?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