Color
#15399e
#15399ergb(21, 57, 158)hsl(224, 77%, 35%)oklch(0.392 0.169 264.5)Colors that go with #15399e
Charcoal, Steel 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 #15399e: softer than #000 and cool enough to feel like part of the same palette.
Steel Blue #4682b4
analogousshippedSteel Blue is #15399e's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Blue #0000ff
shipped6 real palettes, including Procter & Gamble's brand system and CVS's brand system put Blue beside #15399e, as the supporting colour.
Crimson #dc143c
shippedCrimson is paired with #15399e in 7 real palettes, including Behance's brand system and Casper Sleep's brand system, as the accent.
Denim #1560bd
shippedDesigners have shipped Denim with #15399e: 8 real palettes, including Google's brand system and General Mills's brand system, as the accent.
Midnight Blue #191970
shipped11 real palettes, including Fintech Trust and Blue Mono put Midnight Blue beside #15399e, as that palette's text colour.
Royal Blue #4169e1
shippedRoyal Blue is paired with #15399e in 9 real palettes, including Nivea's brand system and NHL's brand system, as the supporting colour.
Olive Green #808000
complementaryOlive Green sits directly opposite #15399e on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Real palettes that use #15399e
Tints & shades
Harmonies
Contrast
| #15399e as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 9.95:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 2.11:1 | 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 #15399e as the background.
Brands using this color
Fonts for this mood
#15399e 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 #15399e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/15399e-9ca2c4-df724e-221f2d-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