Arcade
Open in tool →Hot pink, cyan and acid yellow on near-black — cabinet-glow neon; the black surface is what makes the colours light up.
Color
#effb09
#effb09
hex
#effb09rgb
rgb(239, 251, 9)hsl
hsl(63, 97%, 51%)oklch
oklch(0.947 0.211 113.3)Closest name: Banana Flash (#eefe02)Relative luminance 0.8736
Colors that go with #effb09
Crimson, Violet and Plum 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.
Crimson #dc143c
shippedCrimson is paired with #effb09 in 4 real palettes, including Lay's's brand system and Tequila Sunrise, as the accent — a combination designers have actually shipped, not a computed rotation.
Violet #ee82ee
split-complementshippedViolet is a split-complement of #effb09: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Plum #dda0dd
complementaryPlum sits directly opposite #effb09 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Blue #0000ff
shippedBlue is paired with #effb09 in 3 real palettes, including Robinhood's brand system and Bumble's brand system, as the supporting colour — a combination designers have actually shipped, not a computed rotation.
Charcoal #36454f
neutralshippedCharcoal is the body-text near-black for #effb09: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Deep Pink #ff1493
shippedDeep Pink is paired with #effb09 in 3 real palettes, including Arcade and JetBrains's brand system, as the lead colour — a combination designers have actually shipped, not a computed rotation.
Deep Sky Blue #00bfff
triadicshippedDeep Sky Blue completes a triad with #effb09 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Lime Green #32cd32
analogousshippedLime Green is #effb09's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Real palettes that use #effb09
Tints & shades
Harmonies
Contrast
| #effb09 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 1.14:1 | fail | fail | fail | |
Aaon black | 18.47:1 | pass | pass | pass | Passes 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 #effb09 as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
Palettes built around it
mcpConnect your agent — build around #effb09
live endpointPoint 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.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #effb09 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/effb09-b9bea2-4e8ddf-262d1f-f1eee9?lock=0&style=vibrantWant the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.
Machine-readable: color.md