Color
#042f5d
#042f5drgb(4, 47, 93)hsl(211, 92%, 19%)oklch(0.307 0.094 254.4)Colors that go with #042f5d
Charcoal, Crimson and Slate 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 #042f5d: softer than #000 and cool enough to feel like part of the same palette.
Crimson #dc143c
triadicshippedCrimson completes a triad with #042f5d — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Slate Blue #6a5acd
analogousshippedSlate Blue is #042f5d's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Teal #008080
analogousshippedTeal is #042f5d's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Sienna #a0522d
complementaryshippedSienna sits directly opposite #042f5d on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Amber #ffbf00
shippedAmber is paired with #042f5d in 6 real palettes, including Beach Hut and Southwest Airlines's brand system, as the supporting colour.
Blue #0000ff
shipped12 real palettes, including Alaska Airlines's brand system and Monzo's brand system put Blue beside #042f5d, as the accent.
Blush Pink #e8b4b8
shipped4 real palettes, including Rain Garden and Graphite Mono put Blush Pink beside #042f5d, as the accent.
Real palettes that use #042f5d
Tints & shades
Harmonies
Contrast
| #042f5d as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 13.38:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.57:1 | 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 #042f5d as the background.
Brands using this color
Fonts for this mood
#042f5d 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 #042f5d and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/042f5d-9cabc4-df534e-1f202d-e9f1f1?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