Color
#3f237b
#3f237brgb(63, 35, 123)hsl(259, 56%, 31%)oklch(0.348 0.14 292.1)Colors that go with #3f237b
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 #3f237b: softer than #000 and cool enough to feel like part of the same palette.
Royal Blue #4169e1
analogousshippedRoyal Blue is #3f237b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Blue #0000ff
shipped5 real palettes, including Alaska Airlines's brand system and Procter & Gamble's brand system put Blue beside #3f237b, as the accent.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #3f237b: 5 real palettes, including Purina Pro Plan's brand system and Blue Mono, as the accent.
Crimson #dc143c
shippedCrimson is paired with #3f237b in 7 real palettes, including Casper Sleep's brand system and Marvel's brand system, as the lead colour.
Denim #1560bd
shippedDesigners have shipped Denim with #3f237b: 10 real palettes, including Panasonic's brand system and Bank of America's brand system, as the accent.
Powder Blue #b0e0e6
shippedDesigners have shipped Powder Blue with #3f237b: 4 real palettes, including Glacier and Frost & Ember, as the supporting colour.
Steel Blue #4682b4
shippedDesigners have shipped Steel Blue with #3f237b: 7 real palettes, including FedEx's brand system and Hershey's's brand system, as the accent.
Real palettes that use #3f237b
Tints & shades
Harmonies
Contrast
| #3f237b as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 12.08:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.74:1 | 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 #3f237b 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
#3f237b 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 #3f237b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/3f237b-ad9cc4-dfc74e-2a1f2d-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