Heatwave
Open in tool →Blaze orange and hot yellow with one cold blue — the high-noon palette; use the blue where the eye needs to rest.
Color
#211503
#211503
hex
#211503rgb
rgb(33, 21, 3)hsl
hsl(36, 83%, 7%)oklch
oklch(0.207 0.037 76.9)Closest name: Noir Mystique (#1f180a)Relative luminance 0.0087
Colors that go with #211503
Charcoal, Royal Blue 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.
Charcoal #36454f
neutralshippedCharcoal is the body-text near-black for #211503: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Royal Blue #4169e1
complementaryshippedRoyal Blue sits directly opposite #211503 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Sienna #a0522d
analogousshippedSienna is #211503's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces.
Slate Blue #6a5acd
split-complementshippedSlate Blue is a split-complement of #211503: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Steel Blue #4682b4
split-complementshippedSteel Blue is a split-complement of #211503: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Teal #008080
triadicshippedTeal completes a triad with #211503 — 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 #211503 in 15 real palettes, including Heatwave and Trailhead, as the supporting colour.
Blue #0000ff
shipped23 real palettes, including CVS's brand system and Signal's brand system put Blue beside #211503, as the supporting colour.
Real palettes that use #211503
Tints & shades
Harmonies
Contrast
| #211503 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 17.9:1 | pass | pass | pass | Passes AAA — no fix needed. |
Aaon black | 1.17:1 | 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 #211503 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
#211503 reads as warm, vivid, dark. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #211503
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 #211503 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/211503-c4b99c-62bfcb-2d2d1f-f1eae9?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