Color

#646b87

#646b87
hex#646b87
rgbrgb(100, 107, 135)
hslhsl(228, 15%, 46%)
oklchoklch(0.532 0.045 273.8)
Closest name: Dark Prince (#6b6c89)Relative luminance 0.1497

Colors that go with #646b87

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 #646b87

Tints & shades

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

Harmonies

Complementary

Open in tool →

#878064

#647c87 · #6e6487

#87646b · #6b8764

Split-complementary

Open in tool →

#876e64 · #7c8764

#87647c · #878064 · #64876e

Contrast

#646b87 as textRatioAAAA largeAAAFix
Aaon white
5.26:1passpassfail
  • AAA: use #52586f as the text (7.04:1)
Aaon black
3.99:1failpassfail
  • AA: use #6c7493 as the text (4.56:1)
  • AAA: use #9095ad as the text (7.09:1)
  • AA: or shift the background to #f0f0f0 (4.61:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #646b87 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 #646b87
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 #646b87 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/646b87-9c9fc4-df7c4e-231f2d-e9eff1?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