Color
#21182b
#21182brgb(33, 24, 43)hsl(268, 28%, 13%)oklch(0.23 0.038 305.4)Colors that go with #21182b
Charcoal, Dark Olive Green and Sea Green 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 #21182b: softer than #000 and cool enough to feel like part of the same palette.
Dark Olive Green #556b2f
complementaryshippedDark Olive Green sits directly opposite #21182b 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
split-complementshippedSea Green is a split-complement of #21182b: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Sienna #a0522d
triadicshippedSienna completes a triad with #21182b — 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 #21182b's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Teal #008080
triadicshippedTeal completes a triad with #21182b — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Amber #ffbf00
shippedAmber is paired with #21182b in 18 real palettes, including Blueprint and Google's brand system, as the accent.
Blue #0000ff
shipped22 real palettes, including Warp's brand system and Signal's brand system put Blue beside #21182b, as the supporting colour.
Real palettes that use #21182b
Tints & shades
Harmonies
Contrast
| #21182b as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 17.07:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.23:1 | 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 #21182b as the background.
Brands using this color
Fonts for this mood
#21182b reads as cool, muted, 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 #21182b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/21182b-b39cc4-dfdc4e-2c1f2d-e9eaf1?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