Color

#f3fc55

#f3fc55
hex#f3fc55
rgbrgb(243, 252, 85)
hslhsl(63, 97%, 66%)
oklchoklch(0.955 0.183 112.4)
Closest name: Biohazard Suit (#fbfb4c)Relative luminance 0.8933

Colors that go with #f3fc55

Lilac, Blue and Charcoal 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 →

#5d54fc

#fcb154 · #a0fc54

#54f4fc · #fc54f4

Split-complementary

Open in tool →

#54a0fc · #b154fc

#54fcb1 · #5d54fc · #fc54a0

Contrast

#f3fc55 as textRatioAAAA largeAAAFix
Aaon white
1.11:1failfailfail
  • AA: use #737902 as the text (4.7:1)
  • AAA: use #565a01 as the text (7.35:1)
  • AA: or shift the background to #6e6e6e (4.58:1)
  • AAA: or shift the background to #525252 (7.02:1)
Aaon black
18.87:1passpasspassPasses 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 #f3fc55 as the background.

Brands using this color

mcpConnect your agent — build around #f3fc55
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 #f3fc55 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/f3fc55-b9bea2-4e8ddf-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