Newsprint
Open in tool →Ink-black on warm paper with a single red — the broadsheet hierarchy that lets typography lead.
Color
#b4100e
#b4100e
hex
#b4100ergb
rgb(180, 16, 14)hsl
hsl(1, 86%, 38%)oklch
oklch(0.489 0.193 28.7)Closest name: All Systems Red (#b30103)Relative luminance 0.1011
Colors that go with #b4100e
Royal Blue, Teal and Amber 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 #b4100e — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Teal #008080
complementaryshippedTeal sits directly opposite #b4100e 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 #b4100e in 4 real palettes, including Maple and Ember, as the accent.
Dark Olive Green #556b2f
shippedDark Olive Green shows up next to #b4100e in 5 real palettes, including Olive Grove and Cider, as the lead colour.
Denim #1560bd
shippedDesigners have shipped Denim with #b4100e: 9 real palettes, including Campbell's's brand system and State Farm's brand system, as the accent.
Sea Green #2e8b57
triadicshippedSea Green completes a triad with #b4100e — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash.
Slate Gray #708090
shipped5 real palettes, including Newsprint and Typewriter put Slate Gray beside #b4100e, as the supporting colour.
Charcoal #36454f
neutralshippedCharcoal is the body-text near-black for #b4100e: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy.
Real palettes that use #b4100e
Tints & shades
Harmonies
Contrast
| #b4100e as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 6.95:1 | pass | pass | fail |
|
Aaon black | 3.02:1 | 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 #b4100e as the background.
Brands using this color
Palettes built around it
Fonts for this mood
#b4100e reads as warm, vivid, playful. The font library is tagged with the same vocabulary:
mcpConnect your agent — build around #b4100e
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 #b4100e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/b4100e-c4a19c-62cb9a-2d261f-f1e9ed?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