Color

#42100b

#42100b
hex#42100b
rgbrgb(66, 16, 11)
hslhsl(5, 71%, 15%)
oklchoklch(0.259 0.078 29.2)
Closest name: English Breakfast (#441111)Relative luminance 0.0155

Colors that go with #42100b

Charcoal, Royal Blue 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.

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#0b3d41

#410b22 · #412b0b

#0b4110 · #100b41

Split-complementary

Open in tool →

#0b412b · #0b2241

#22410b · #0b3d41 · #2b0b41

Contrast

#42100b as textRatioAAAA largeAAAFix
Aaon white
16.02:1passpasspassPasses AAA — no fix needed.
Aaon black
1.31:1failfailfail
  • AA: use #db3829 as the text (4.61:1)
  • AAA: use #e6756b as the text (7.12:1)
  • AA: or shift the background to #8a8a8a (4.64:1)
  • AAA: or shift the background to #adadad (7.14:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #42100b as the background.

Brands using this color

Fonts for this mood

#42100b reads as warm, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #42100b
live endpoint

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.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #42100b and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/42100b-c4a49c-62cba1-2d261f-f1e9ec?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md