Color
#645a81
#645a81rgb(100, 90, 129)hsl(255, 18%, 43%)oklch(0.493 0.062 295.8)Colors that go with #645a81
Charcoal, Sea Green and Copper 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 #645a81: 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 #645a81: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Copper #b87333
shippedDesigners have shipped Copper with #645a81: 4 real palettes, including Dusk and Desert Road, as the accent.
Crimson #dc143c
shippedCrimson is paired with #645a81 in 12 real palettes, including Wells Fargo's brand system and Marvel's brand system, as the lead colour.
Denim #1560bd
shippedDesigners have shipped Denim with #645a81: 11 real palettes, including HP's brand system and The New York Times's brand system, as the accent.
Firebrick #b22222
shippedDesigners have shipped Firebrick with #645a81: 6 real palettes, including Newsprint and Wendy's's brand system, as the lead colour.
Goldenrod #daa520
shippedGoldenrod shows up next to #645a81 in 4 real palettes, including Open House and Mid-Century, as the accent.
Medium Sea Green #3cb371
shippedMedium Sea Green is paired with #645a81 in 4 real palettes, including Fintech Trust and Console Light, as the accent.
Real palettes that use #645a81
Tints & shades
Harmonies
Contrast
| #645a81 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 6.32:1 | pass | pass | fail |
|
Aaon black | 3.32:1 | 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 #645a81 as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
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 #645a81 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/645a81-ab9cc4-dfbd4e-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