Color

#4b378b

#4b378b
hex#4b378b
rgbrgb(75, 55, 139)
hslhsl(254, 43%, 38%)
oklchoklch(0.406 0.134 290.1)
Closest name: darkslateblue (#483d8b)Relative luminance 0.0609

Colors that go with #4b378b

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 →

#778b37

#374d8b · #74378b

#8b4b37 · #378b4b

Split-complementary

Open in tool →

#8b7437 · #4d8b37

#8b374d · #778b37 · #378b74

Contrast

#4b378b as textRatioAAAA largeAAAFix
Aaon white
9.47:1passpasspassPasses AAA — no fix needed.
Aaon black
2.22:1failfailfail
  • AA: use #7b66c2 as the text (4.52:1)
  • AAA: use #9e8ed2 as the text (7.25:1)
  • AA: or shift the background to #b3b3b3 (4.51:1)
  • AAA: or shift the background to #dedede (7.04:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #4b378b 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

#4b378b reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #4b378b
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 #4b378b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/4b378b-aa9cc4-dfbb4e-291f2d-e9ebf1?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