# #effc3b

A color — vivid. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#effc3b`
- RGB: rgb(239, 252, 59)
- HSL: hsl(64, 97%, 61%)
- OKLCH: oklch(0.951 0.198 113.6)
- Relative luminance: 0.8829
- Nearest named color: Banana Bandanna (#f8f739, Δ 1.632) — https://brandsweets.com/colors/banana-bandanna
- Moods: vivid
- Page: https://brandsweets.com/colors/effc3b

## Tints & shades

- Tints (toward white): #f1fc4f, #f2fd5e, #f4fd72, #f5fd86, #f7fd9b, #f8feaa, #fafebe, #fbfed2, #fdffe1, #fefff5
- Shades (toward black): #edfc1d, #ebfb04, #cfdd03, #b2bf03, #9ba603, #7f8802, #636902, #464b01, #2f3201, #131400

## Harmonies

- Complementary: #483bfc
- Analogous: #fca83b, #8ffc3b
- Triadic: #3beffc, #fc3bef
- Split-complementary: #3b8ffc, #a83bfc
- Tetradic: #3bfca8, #483bfc, #fc3b8f

## Colors that go with #effc3b

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Blue** #0000ff [pool] — 4 real palettes, including Snapchat's brand system and Robinhood's brand system put Blue beside #effc3b, as the supporting colour. Seen in: Snapchat (https://brandsweets.com/colors/brands/snapchat-com), Robinhood (https://brandsweets.com/colors/brands/robinhood-com), Bumble (https://brandsweets.com/colors/brands/bumble-com), Binance (https://brandsweets.com/colors/brands/binance-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #effc3b in 7 real palettes, including Ferrari's brand system and Lay's's brand system, as the lead colour. Seen in: Ferrari (https://brandsweets.com/colors/brands/ferrari-com), Lay's (https://brandsweets.com/colors/brands/lays-com), Tequila Sunrise (https://brandsweets.com/palettes/vivid#tequila-sunrise), Diner (https://brandsweets.com/palettes/vivid#diner). — https://brandsweets.com/colors/crimson
- **Red** #ff0000 [pool] — Red is paired with #effc3b in 4 real palettes, including Heineken's brand system and Paddle's brand system, as the accent. Seen in: Heineken (https://brandsweets.com/colors/brands/heineken-com), Paddle (https://brandsweets.com/colors/brands/paddle-com), Phantom: The money app that'll take you placesLogo PhantomLogo PhantomLogo Phantom (https://brandsweets.com/colors/brands/phantom-com), Wise (https://brandsweets.com/colors/brands/wise-com). — https://brandsweets.com/colors/red
- **Taupe** #483c32 [pool] — Taupe is paired with #effc3b in 6 real palettes, including Calvin Klein's brand system and Tommy Hilfiger's brand system, as the lead colour. Seen in: Calvin Klein (https://brandsweets.com/colors/brands/calvinklein-us), Tommy Hilfiger (https://brandsweets.com/colors/brands/tommy-com), Crayon Box (https://brandsweets.com/palettes/playful#crayon-box), Citrus Grove (https://brandsweets.com/palettes/warm#citrus-grove). — https://brandsweets.com/colors/taupe
- **Violet** #ee82ee [harmony, pool: split] — Violet is a split-complement of #effc3b: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Gumroad (https://brandsweets.com/colors/brands/gumroad-com). — https://brandsweets.com/colors/violet
- **Plum** #dda0dd [harmony: complementary] — Plum sits directly opposite #effc3b on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. — https://brandsweets.com/colors/plum
- **Charcoal** #36454f [role, pool] — Charcoal is the body-text near-black for #effc3b: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy. Seen in: Zendesk (https://brandsweets.com/colors/brands/zendesk-com), Lagoon (https://brandsweets.com/palettes/vivid#lagoon). — https://brandsweets.com/colors/charcoal
- **Cornflower Blue** #6495ed [harmony, pool: split] — Cornflower Blue is a split-complement of #effc3b: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: NBA (https://brandsweets.com/colors/brands/nba-com). — https://brandsweets.com/colors/cornflowerblue

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 1.13:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #717902 (4.73:1); AA: background → #6e6e6e (4.53:1); AAA: text → #545a01 (7.39:1); AAA: background → #4f4f4f (7.28:1)
- On black (#000000): 18.66:1 — AA pass, AA-large pass, AAA pass

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/effc3b-b9bea2-4e8adf-262d1f-f1eee9?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#effc3b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.