Color

#663cd3

#663cd3
hex#663cd3
rgbrgb(102, 60, 211)
hslhsl(257, 63%, 53%)
oklchoklch(0.499 0.216 288.8)
Closest name: Hokkaido Lavender (#7736d9)Relative luminance 0.1076

Colors that go with #663cd3

Charcoal, Royal Blue 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#a8d33c

#3c5cd3 · #b23cd3

#d3663c · #3cd366

Split-complementary

Open in tool →

#d3b23c · #5cd33c

#d33c5c · #a8d33c · #3cd3b2

Contrast

#663cd3 as textRatioAAAA largeAAAFix
Aaon white
6.66:1passpassfail
  • AAA: use #6033d1 as the text (7.26:1)
Aaon black
3.15:1failpassfail
  • AA: use #8461db as the text (4.71:1)
  • AAA: use #a186e4 as the text (7.05:1)
  • AA: or shift the background to #d6d6d6 (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 #663cd3 as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#663cd3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #663cd3
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 #663cd3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/663cd3-ac9cc4-dfc24e-291f2d-e9ebf1?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