Frost & Ember
Open in tool →Navy and frost with one ember red — the classic cold-with-a-warm-accent structure, borrowed from a thousand ski posters.
Color
#243151
#243151
hex
#243151rgb
rgb(36, 49, 81)hsl
hsl(223, 38%, 23%)oklch
oklch(0.318 0.06 266.3)Closest name: Deep Sea Base (#2c2c57)Relative luminance 0.0317
Colors that go with #243151
Dark Olive Green, Sea Green and Sienna 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.
Dark Olive Green #556b2f
complementaryshippedDark Olive Green sits directly opposite #243151 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Sea Green #2e8b57
triadicshippedSea Green completes a triad with #243151 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Sienna #a0522d
split-complementshippedSienna is a split-complement of #243151: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Slate Blue #6a5acd
analogousshippedSlate Blue is #243151's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Steel Blue #4682b4
analogousshippedSteel Blue is #243151'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 #243151 in 4 real palettes, including Beach Hut and Wikipedia's brand system, as the supporting colour — a combination designers have actually shipped, not a computed rotation.
Blue #0000ff
shippedBlue is paired with #243151 in 12 real palettes, including Sketch's brand system and Monzo's brand system, as the accent — a combination designers have actually shipped, not a computed rotation.
White Smoke #f5f5f5
neutralWhite Smoke is the surface for #243151: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy.
Real palettes that use #243151
Tints & shades
Harmonies
Contrast
| #243151 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 12.86:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.63:1 | 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 #243151 as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
Palettes built around it
Fonts for this mood
#243151 reads as cool, dark, luxury. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #243151
live endpointPoint 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.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #243151 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/243151-9ca3c4-df704e-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