Color

#efff3d

#efff3d
hex#efff3d
rgbrgb(239, 255, 61)
hslhsl(65, 100%, 62%)
oklchoklch(0.957 0.2 114.4)
Closest name: Busy Bee (#f4ff00)Relative luminance 0.9021

Tints & shades

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

Harmonies

Complementary

Open in tool →

#4d3dff

#ffae3d · #8eff3d

#3defff · #ff3def

Split-complementary

Open in tool →

#3d8eff · #ae3dff

#3dffae · #4d3dff · #ff3d8e

Contrast

#efff3d as textRatioAAAA largeAAAFix
Aaon white
1.1:1failfailfail
  • AA: use #707a00 as the text (4.7:1)
  • AAA: use #545c00 as the text (7.22:1)
  • AA: or shift the background to #6e6e6e (4.62:1)
  • AAA: or shift the background to #525252 (7.09:1)
Aaon black
19.04:1passpasspassPasses 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 #efff3d as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

mcpConnect your agent — build around #efff3d
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 #efff3d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/efff3d-b8bea2-4e88df-262d1f-f1eee9?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