Color
#331b74
#331b74rgb(51, 27, 116)hsl(256, 62%, 28%)oklch(0.317 0.142 287.8)Colors that go with #331b74
Charcoal, Royal Blue and Blue 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 #331b74: softer than #000 and cool enough to feel like part of the same palette.
Royal Blue #4169e1
analogousshippedRoyal Blue is #331b74's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Blue #0000ff
shippedBlue is paired with #331b74 in 5 real palettes, including Pepsi's brand system and Sketch's brand system, as the supporting colour — a combination designers have actually shipped, not a computed rotation.
Crimson #dc143c
shippedCrimson is paired with #331b74 in 4 real palettes, including Casper Sleep's brand system and Nintendo's brand system, as the lead colour — a combination designers have actually shipped, not a computed rotation.
Denim #1560bd
shippedDenim is paired with #331b74 in 6 real palettes, including Bank of America's brand system and Hasbro's brand system, as the accent — a combination designers have actually shipped, not a computed rotation.
Steel Blue #4682b4
shippedSteel Blue is paired with #331b74 in 7 real palettes, including Hershey's's brand system and Glacier, as the accent — a combination designers have actually shipped, not a computed rotation.
Olive Green #808000
complementaryOlive Green sits directly opposite #331b74 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Light Sea Green #20b2aa
shippedLight Sea Green is paired with #331b74 in 3 real palettes, including Confluent's brand system and Taco Bell's brand system, as the accent — a combination designers have actually shipped, not a computed rotation.
Real palettes that use #331b74
Tints & shades
Harmonies
Contrast
| #331b74 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 13.55:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.55:1 | 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 #331b74 as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
Fonts for this mood
#331b74 reads as cool, vivid, dark. 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 #331b74 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/331b74-ab9cc4-dfbf4e-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