Color

#51557b

#51557b
hex#51557b
rgbrgb(81, 85, 123)
hslhsl(234, 21%, 40%)
oklchoklch(0.462 0.062 279)
Closest name: Deep Indigo (#4c567a)Relative luminance 0.0968

Colors that go with #51557b

Steel Blue, Teal 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.

Real palettes that use #51557b

Tints & shades

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

Harmonies

Complementary

Open in tool →

#7b7751

#516a7b · #62517b

#7b5155 · #557b51

Split-complementary

Open in tool →

#7b6251 · #6a7b51

#7b516a · #7b7751 · #517b62

Contrast

#51557b as textRatioAAAA largeAAAFix
Aaon white
7.15:1passpasspassPasses AAA — no fix needed.
Aaon black
2.94:1failfailfail
  • AA: use #6e73a0 as the text (4.62:1)
  • AAA: use #9094b6 as the text (7.1:1)
  • AA: or shift the background to #cfcfcf (4.59:1)
  • AAA: or shift the background to #ffffff (7.15:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #51557b as the background.

Brands using this color

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

mcpConnect your agent — build around #51557b
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 #51557b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/51557b-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