Color
#591bc5
#591bc5rgb(89, 27, 197)hsl(262, 76%, 44%)oklch(0.44 0.23 289.3)Colors that go with #591bc5
Olive Green, Charcoal and Slate Gray 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.
Olive Green #808000
complementaryOlive Green sits directly opposite #591bc5 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #591bc5: softer than #000 and cool enough to feel like part of the same palette.
Slate Gray #708090
shippedSlate Gray is paired with #591bc5 in 3 real palettes, including Indigo SaaS and Ink & Paper, as the supporting colour — a combination designers have actually shipped, not a computed rotation.
Forest Green #228b22
split-complementForest Green is a split-complement of #591bc5: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Dark Orchid #9932cc
analogousshippedDark Orchid is #591bc5's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Sienna #a0522d
triadicSienna completes a triad with #591bc5 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Sea Green #2e8b57
triadicSea Green completes a triad with #591bc5 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Royal Blue #4169e1
analogousRoyal Blue is #591bc5'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 #591bc5
Tints & shades
Harmonies
Contrast
| #591bc5 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 8.79:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 2.39:1 | fail | fail | fail |
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #591bc5 as the background.
Brands using this color
Fonts for this mood
#591bc5 reads as cool, vivid, technical. 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 #591bc5 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/591bc5-af9cc4-dfce4e-2a1f2d-e9eaf1?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