Color

#66deff

#66deff
hex#66deff
rgbrgb(102, 222, 255)
hslhsl(193, 100%, 70%)
oklchoklch(0.844 0.116 218.7)
Closest name: lightskyblue (#87cefa)Relative luminance 0.6229

Colors that go with #66deff

Charcoal, Deep Sky Blue and Crimson 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 →

#ff8766

#66ffd4 · #6691ff

#ff66de · #deff66

Split-complementary

Open in tool →

#ff6691 · #ffd466

#d466ff · #ff8766 · #91ff66

Contrast

#66deff as textRatioAAAA largeAAAFix
Aaon white
1.56:1failfailfail
  • AA: use #0080a3 as the text (4.55:1)
  • AAA: use #00607a as the text (7.11:1)
  • AA: or shift the background to #575757 (4.63:1)
  • AAA: or shift the background to #3b3b3b (7.18:1)
Aaon black
13.46:1passpasspassPasses AAA — no fix needed.

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #66deff as the background.

Brands using this color

Fonts for this mood

#66deff reads as cool, vivid, light. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #66deff
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 #66deff and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/66deff-a2b5be-df4e75-1f242d-e9f1ef?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