Color

#42efff

#42efff
hex#42efff
rgbrgb(66, 239, 255)
hslhsl(185, 100%, 63%)
oklchoklch(0.874 0.136 204.4)
Closest name: Aqua (#0ff0fe)Relative luminance 0.7011

Tints & shades

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

Harmonies

Complementary

Open in tool →

#ff5242

#42ffb0 · #4291ff

#ff42ef · #efff42

Split-complementary

Open in tool →

#ff4291 · #ffb042

#b042ff · #ff5242 · #91ff42

Contrast

#42efff as textRatioAAAA largeAAAFix
Aaon white
1.4:1failfailfail
  • AA: use #00838f as the text (4.52:1)
  • AAA: use #00626b as the text (7.1:1)
  • AA: or shift the background to #5e5e5e (4.64:1)
  • AAA: or shift the background to #424242 (7.19:1)
Aaon black
15.02:1passpasspassPasses 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 #42efff 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

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

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

tool url/palettes/new/42efff-a2b8be-df4e88-1f262d-e9f1ee?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