Color

#5b66cd

#5b66cd
hex#5b66cd
rgbrgb(91, 102, 205)
hslhsl(234, 53%, 58%)
oklchoklch(0.554 0.158 275.4)
Closest name: God of Rain (#4466cc)Relative luminance 0.1613

Colors that go with #5b66cd

Charcoal, Sea Green 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 →

#cdc15b

#5b9fcd · #895bcd

#cd5b66 · #66cd5b

Split-complementary

Open in tool →

#cd895b · #9fcd5b

#cd5b9f · #cdc15b · #5bcd89

Contrast

#5b66cd as textRatioAAAA largeAAAFix
Aaon white
4.97:1passpassfail
  • AAA: use #3c49c3 as the text (7.16:1)
Aaon black
4.23:1failpassfail
  • AA: use #636ecf as the text (4.66:1)
  • AAA: use #8a92db as the text (7.22:1)
  • AA: or shift the background to #f5f5f5 (4.56:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #5b66cd as the background.

Brands using this color

Fonts for this mood

#5b66cd reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #5b66cd
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 #5b66cd and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/5b66cd-9d9cc4-df8a4e-241f2d-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