Color
#3f588d
#3f588drgb(63, 88, 141)hsl(221, 38%, 40%)oklch(0.466 0.092 264)Colors that go with #3f588d
Charcoal, Sea Green and Steel 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 #3f588d: softer than #000 and cool enough to feel like part of the same palette.
Sea Green #2e8b57
triadicshippedSea Green completes a triad with #3f588d — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Steel Blue #4682b4
analogousshippedSteel Blue is #3f588d's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Amber #ffbf00
shippedAmber is paired with #3f588d in 6 real palettes, including McDonald's's brand system and Warner Bros.'s brand system, as the lead colour.
Blue #0000ff
shipped6 real palettes, including Tesco's brand system and CVS's brand system put Blue beside #3f588d, as the supporting colour.
Cornflower Blue #6495ed
shippedDesigners have shipped Cornflower Blue with #3f588d: 4 real palettes, including Coca-Cola's brand system and Gopro's brand system, as the supporting colour.
Crimson #dc143c
shippedCrimson is paired with #3f588d in 15 real palettes, including Walgreens's brand system and Costco's brand system, as the lead colour.
Deep Sky Blue #00bfff
shippedDesigners have shipped Deep Sky Blue with #3f588d: 4 real palettes, including Venmo's brand system and Deep Water, as the supporting colour.
Real palettes that use #3f588d
Tints & shades
Harmonies
Contrast
| #3f588d as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 7.02:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 2.99:1 | 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 #3f588d 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
#3f588d 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 #3f588d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/3f588d-9ca4c4-df6b4e-211f2d-e9eff1?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