Color

#647c90

#647c90
hex#647c90
rgbrgb(100, 124, 144)
hslhsl(207, 18%, 48%)
oklchoklch(0.575 0.042 243.7)
Closest name: Citadel (#6a7f8b)Relative luminance 0.1914

Colors that go with #647c90

Charcoal, Copper 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.

Real palettes that use #647c90

Tints & shades

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

Harmonies

Complementary

Open in tool →

#907864

#64908e · #646790

#90647d · #7d9064

Split-complementary

Open in tool →

#906467 · #908e64

#8e6490 · #907864 · #679064

Contrast

#647c90 as textRatioAAAA largeAAAFix
Aaon white
4.35:1failpassfail
  • AA: use #60778a as the text (4.66:1)
  • AAA: use #495b69 as the text (7.04:1)
  • AA: or shift the background to #0a0a0a (4.55:1)
Aaon black
4.83:1passpassfail
  • AAA: use #8498a9 as the text (7.05:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #647c90 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 #647c90
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 #647c90 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/647c90-9cadc4-df4e53-1f212d-e9f1f1?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