Color

#66b3ff

#66b3ff
hex#66b3ff
rgbrgb(102, 179, 255)
hslhsl(210, 100%, 70%)
oklchoklch(0.749 0.134 249.8)
Closest name: Fennel Flower (#77aaff)Relative luminance 0.4228

Tints & shades

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

Harmonies

Complementary

Open in tool →

#ffb366

#66ffff · #6666ff

#ff66b3 · #b3ff66

Split-complementary

Open in tool →

#ff6666 · #ffff66

#ff66ff · #ffb366 · #66ff66

Contrast

#66b3ff as textRatioAAAA largeAAAFix
Aaon white
2.22:1failfailfail
  • AA: use #0073e6 as the text (4.57:1)
  • AAA: use #0057ad as the text (7.08:1)
  • AA: or shift the background to #424242 (4.53:1)
  • AAA: or shift the background to #212121 (7.25:1)
Aaon black
9.46:1passpasspassPasses 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 #66b3ff as the background.

Brands using this color

Fonts for this mood

#66b3ff reads as cool, vivid, light. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #66b3ff
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #66b3ff and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/66b3ff-9cabc4-df514e-1f202d-e9f1f1?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