Color

#4578bf

#4578bf
hex#4578bf
rgbrgb(69, 120, 191)
hslhsl(215, 49%, 51%)
oklchoklch(0.571 0.123 257)
Closest name: Haddock’s Sweater (#277aba)Relative luminance 0.1846

Colors that go with #4578bf

Charcoal, Sea Green and Copper 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 →

#bf8c45

#45b5bf · #4f45bf

#bf4578 · #78bf45

Split-complementary

Open in tool →

#bf4f45 · #b5bf45

#bf45b5 · #bf8c45 · #45bf4f

Contrast

#4578bf as textRatioAAAA largeAAAFix
Aaon white
4.48:1failpassfail
  • AA: use #4175be as the text (4.65:1)
  • AAA: use #315990 as the text (7.09:1)
  • AA: or shift the background to #050505 (4.55:1)
Aaon black
4.69:1passpassfail
  • AAA: use #7299cf as the text (7.17:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #4578bf as the background.

Brands using this color

Fonts for this mood

#4578bf reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #4578bf
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 #4578bf and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/4578bf-9ca8c4-df5d4e-201f2d-e9f0f1?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