Color
#21555e
#21555ergb(33, 85, 94)hsl(189, 48%, 25%)oklch(0.419 0.057 210.7)Colors that go with #21555e
Steel Blue, Rust 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.
Steel Blue #4682b4
analogousshippedSteel Blue is #21555e's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Rust #b7410e
complementaryshippedRust sits directly opposite #21555e on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Blue #0000ff
shipped9 real palettes, including Jeep's brand system and Alaska Airlines's brand system put Blue beside #21555e, as the accent.
Cadet Blue #5f9ea0
shippedDesigners have shipped Cadet Blue with #21555e: 4 real palettes, including Paper & Pine and Open House, as the supporting colour.
Copper #b87333
shippedDesigners have shipped Copper with #21555e: 4 real palettes, including Desert Road and Dusk, as the lead colour.
Crimson #dc143c
shippedCrimson is paired with #21555e in 6 real palettes, including Codecademy's brand system and Gemstone, as the accent.
Denim #1560bd
shippedDesigners have shipped Denim with #21555e: 8 real palettes, including Hinge's brand system and Jack Daniel's's brand system, as the accent.
White Smoke #f5f5f5
neutralWhite Smoke is the surface for #21555e: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy.
Real palettes that use #21555e
Tints & shades
Harmonies
Contrast
| #21555e as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 8.31:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 2.53:1 | 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 #21555e as the background.
Brands using this color
Fonts for this mood
#21555e reads as cool, dark, luxury. 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 #21555e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
/palettes/new/21555e-a2b7be-df4e7e-1f252d-e9f1ee?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