Color

#6537b3

#6537b3
hex#6537b3
rgbrgb(101, 55, 179)
hslhsl(262, 53%, 46%)
oklchoklch(0.465 0.185 295.2)
Closest name: rebeccapurple (#663399)Relative luminance 0.0875

Colors that go with #6537b3

Charcoal, Royal Blue and Sea 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#86b337

#3748b3 · #a337b3

#b36537 · #37b365

Split-complementary

Open in tool →

#b3a337 · #48b337

#b33748 · #86b337 · #37b3a3

Contrast

#6537b3 as textRatioAAAA largeAAAFix
Aaon white
7.63:1passpasspassPasses AAA — no fix needed.
Aaon black
2.75:1failfailfail
  • AA: use #885fce as the text (4.57:1)
  • AAA: use #a586da as the text (7.02:1)
  • AA: or shift the background to #c7c7c7 (4.52:1)
  • AAA: or shift the background to #f5f5f5 (7:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #6537b3 as the background.

Brands using this color

Fonts for this mood

#6537b3 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #6537b3
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 #6537b3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/6537b3-af9cc4-dfce4e-2a1f2d-e9eaf1?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