Color
#664eb7
#664eb7rgb(102, 78, 183)hsl(254, 42%, 51%)oklch(0.504 0.159 290)Colors that go with #664eb7
Charcoal, Sea Green and Amber 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 #664eb7: softer than #000 and cool enough to feel like part of the same palette.
Sea Green #2e8b57
split-complementshippedSea Green is a split-complement of #664eb7: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Amber #ffbf00
shippedAmber is paired with #664eb7 in 5 real palettes, including Warner Bros.'s brand system and Wikipedia's brand system, as the accent.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #664eb7: 4 real palettes, including Fintech Trust and Zillow's brand system, as the lead colour.
Cornflower Blue #6495ed
shippedDesigners have shipped Cornflower Blue with #664eb7: 5 real palettes, including Coca-Cola's brand system and Gopro's brand system, as the supporting colour.
Crimson #dc143c
shippedCrimson is paired with #664eb7 in 9 real palettes, including Marvel's brand system and Netflix's brand system, as the accent.
Firebrick #b22222
shippedDesigners have shipped Firebrick with #664eb7: 4 real palettes, including Campbell's's brand system and Datadog's brand system, as the supporting colour.
Light Sky Blue #87cefa
shippedLight Sky Blue is paired with #664eb7 in 4 real palettes, including Sentry's brand system and Calm's brand system, as the accent.
Real palettes that use #664eb7
Tints & shades
Harmonies
Contrast
| #664eb7 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 6.29:1 | pass | pass | fail |
|
Aaon black | 3.34:1 | 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 #664eb7 as the background.
Brands using this color
Fonts for this mood
#664eb7 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 #664eb7 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/664eb7-aa9cc4-dfbb4e-291f2d-e9ebf1?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