Color

#515b9a

#515b9a
hex#515b9a
rgbrgb(81, 91, 154)
hslhsl(232, 31%, 46%)
oklchoklch(0.492 0.101 275.2)
Closest name: Bellflower (#5d66aa)Relative luminance 0.1156

Colors that go with #515b9a

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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#9a9051

#517f9a · #6c519a

#9a515b · #5b9a51

Split-complementary

Open in tool →

#9a6c51 · #7f9a51

#9a517f · #9a9051 · #519a6c

Contrast

#515b9a as textRatioAAAA largeAAAFix
Aaon white
6.34:1passpassfail
  • AAA: use #4a538c as the text (7.22:1)
Aaon black
3.31:1failpassfail
  • AA: use #6972b0 as the text (4.63:1)
  • AAA: use #8d95c3 as the text (7.22:1)
  • AA: or shift the background to #dbdbdb (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 #515b9a 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 #515b9a
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 #515b9a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/515b9a-9c9dc4-df864e-231f2d-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