Color

#666da3

#666da3
hex#666da3
rgbrgb(102, 109, 163)
hslhsl(233, 25%, 52%)
oklchoklch(0.552 0.084 277.6)
Closest name: Loch Ness (#5f6db0)Relative luminance 0.1641

Tints & shades

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

Harmonies

Complementary

Open in tool →

#a39c66

#668ca3 · #7d66a3

#a3666d · #6da366

Split-complementary

Open in tool →

#a37d66 · #8ca366

#a3668c · #a39c66 · #66a37d

Contrast

#666da3 as textRatioAAAA largeAAAFix
Aaon white
4.91:1passpassfail
  • AAA: use #4e5583 as the text (7.12:1)
Aaon black
4.28:1failpassfail
  • AA: use #6c73a7 as the text (4.65:1)
  • AAA: use #8f95bc as the text (7.19:1)
  • AA: or shift the background to #f7f7f7 (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 #666da3 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 #666da3
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 #666da3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/666da3-9c9cc4-df884e-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