Color

#666c8a

#666c8a
hex#666c8a
rgbrgb(102, 108, 138)
hslhsl(230, 15%, 47%)
oklchoklch(0.538 0.048 275.9)
Closest name: Dark Prince (#6b6c89)Relative luminance 0.1538

Colors that go with #666c8a

Charcoal, Sea Green and Dark Olive Green 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 #666c8a

Tints & shades

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

Harmonies

Complementary

Open in tool →

#8a8466

#667e8a · #72668a

#8a666c · #6c8a66

Split-complementary

Open in tool →

#8a7266 · #7e8a66

#8a667e · #8a8466 · #668a72

Contrast

#666c8a as textRatioAAAA largeAAAFix
Aaon white
5.15:1passpassfail
  • AAA: use #52576f as the text (7.11:1)
Aaon black
4.08:1failpassfail
  • AA: use #6c7393 as the text (4.51:1)
  • AAA: use #9094ad as the text (7.03:1)
  • AA: or shift the background to #f0f0f0 (4.52:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #666c8a 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 #666c8a
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 #666c8a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/666c8a-9c9ec4-df814e-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