Newsprint
Open in tool →Ink-black on warm paper with a single red — the broadsheet hierarchy that lets typography lead.
Color
#b21d06
#b21d06
hex
#b21d06rgb
rgb(178, 29, 6)hsl
hsl(8, 93%, 36%)oklch
oklch(0.491 0.185 31.3)Closest name: firebrick (#b22222)Relative luminance 0.1036
Colors that go with #b21d06
Royal Blue, Steel Blue and Teal 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.
Royal Blue #4169e1
triadicshippedRoyal Blue completes a triad with #b21d06 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Steel Blue #4682b4
split-complementshippedSteel Blue is a split-complement of #b21d06: nearly opposite, so it still pops against it, without the vibrating edge of a true complement.
Teal #008080
complementaryshippedTeal sits directly opposite #b21d06 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 #b21d06 in 5 real palettes, including Ember and Maple, as the accent.
Blue #0000ff
shipped4 real palettes, including Tim Hortons's brand system and Dunkin''s brand system put Blue beside #b21d06, as the accent.
Cobalt Blue #0047ab
shippedDesigners have shipped Cobalt Blue with #b21d06: 4 real palettes, including MLB's brand system and Behance's brand system, as the accent.
Dark Olive Green #556b2f
shippedDark Olive Green shows up next to #b21d06 in 5 real palettes, including Olive Grove and Cider, as the lead colour.
Charcoal #36454f
neutralshippedCharcoal is the body-text near-black for #b21d06: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Real palettes that use #b21d06
Tints & shades
Harmonies
Contrast
| #b21d06 as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 6.84:1 | pass | pass | fail |
|
Aaon black | 3.07:1 | fail | pass | fail |
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #b21d06 as the background.
Brands using this color
Palettes built around it
Fonts for this mood
#b21d06 reads as warm, vivid, playful. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #b21d06
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 #b21d06 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/b21d06-c4a69c-62cba6-2d271f-f1e9ec?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