Color

#42aaff

#42aaff
hex#42aaff
rgbrgb(66, 170, 255)
hslhsl(207, 100%, 63%)
oklchoklch(0.717 0.156 247.1)
Closest name: Cerulean (#55aaee)Relative luminance 0.3713

Tints & shades

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

Harmonies

Complementary

Open in tool →

#ff9742

#42fff6 · #424cff

#ff42aa · #aaff42

Split-complementary

Open in tool →

#ff424c · #fff642

#f642ff · #ff9742 · #4cff42

Contrast

#42aaff as textRatioAAAA largeAAAFix
Aaon white
2.49:1failfailfail
  • AA: use #0076d6 as the text (4.6:1)
  • AAA: use #005aa3 as the text (7.02:1)
  • AA: or shift the background to #383838 (4.7:1)
  • AAA: or shift the background to #171717 (7.19:1)
Aaon black
8.43:1passpasspassPasses 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 #42aaff as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#42aaff reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #42aaff
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 #42aaff and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/42aaff-9cadc4-df4e53-1f212d-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