Color
#3666bf
#3666bfrgb(54, 102, 191)hsl(219, 56%, 48%)oklch(0.524 0.149 261.5)Colors that go with #3666bf
Charcoal, Sea Green and Sienna 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.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #3666bf: softer than #000 and cool enough to feel like part of the same palette.
Sea Green #2e8b57
triadicshippedSea Green completes a triad with #3666bf — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Sienna #a0522d
complementaryshippedSienna sits directly opposite #3666bf on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Amber #ffbf00
shippedAmber is paired with #3666bf in 10 real palettes, including Warner Bros.'s brand system and Wikipedia's brand system, as the accent.
Blue #0000ff
shipped16 real palettes, including Pixar's brand system and Activision's brand system put Blue beside #3666bf, as the accent.
Cornflower Blue #6495ed
shippedDesigners have shipped Cornflower Blue with #3666bf: 7 real palettes, including Coca-Cola's brand system and NBA's brand system, as the supporting colour.
Crimson #dc143c
shippedCrimson is paired with #3666bf in 20 real palettes, including Netflix's brand system and Ulta Beauty's brand system, as the lead colour.
Deep Sky Blue #00bfff
shippedDesigners have shipped Deep Sky Blue with #3666bf: 7 real palettes, including Venmo's brand system and Astro's brand system, as the supporting colour.
Real palettes that use #3666bf
Tints & shades
Harmonies
Contrast
| #3666bf as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 5.51:1 | pass | pass | fail |
|
Aaon black | 3.81:1 | fail | pass | fail |
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3666bf as the background.
Brands using this color
- Bingaccent · #3366bb · Δ0.704
- Campbell'saccent · #3860be · Δ1.561
- Coca-Colaaccent · #3860be · Δ1.561
- Guinnessaccent · #3860be · Δ1.561
- Heinzaccent · #3860be · Δ1.561
- Hingeaccent · #3860be · Δ1.561
- Jack Daniel'sprimary · #3860be · Δ1.561
- L'Oréalaccent · #3860be · Δ1.561
- Maybellineaccent · #3860be · Δ1.561
- Netflixaccent · #3860be · Δ1.561
- Nikonsecondary · #3860be · Δ1.561
- Paramount+primary · #3860be · Δ1.561
- Pixarsecondary · #3860be · Δ1.561
- Starlinksecondary · #3860be · Δ1.561
- Ulta Beautysecondary · #3860be · Δ1.561
- Victoria's Secretaccent · #3860be · Δ1.561
- Warner Bros.secondary · #3860be · Δ1.561
Fonts for this mood
#3666bf reads as cool, modern. The font library is tagged with the same vocabulary:
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.
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
›analyze #3666bf and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/3666bf-9ca5c4-df664e-211f2d-e9f0f1?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