Color

#666fa9

#666fa9
hex#666fa9
rgbrgb(102, 111, 169)
hslhsl(232, 28%, 53%)
oklchoklch(0.559 0.091 276.3)
Closest name: Loch Ness (#5f6db0)Relative luminance 0.1706

Tints & shades

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

Harmonies

Complementary

Open in tool →

#a9a066

#6690a9 · #7e66a9

#a9666f · #6fa966

Split-complementary

Open in tool →

#a97e66 · #90a966

#a96690 · #a9a066 · #66a97e

Contrast

#666fa9 as textRatioAAAA largeAAAFix
Aaon white
4.76:1passpassfail
  • AAA: use #4d5589 as the text (7.06:1)
Aaon black
4.41:1failpassfail
  • AA: use #6972ab as the text (4.6:1)
  • AAA: use #8d93bf as the text (7.06:1)
  • AA: or shift the background to #fafafa (4.56:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #666fa9 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 #666fa9
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #666fa9 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/666fa9-9c9dc4-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