Color

#0d3d40

#0d3d40
hex#0d3d40
rgbrgb(13, 61, 64)
hslhsl(184, 66%, 15%)
oklchoklch(0.331 0.05 201.2)
Closest name: Rich Black (#004040)Relative luminance 0.0379

Colors that go with #0d3d40

Crimson, Sienna and Steel 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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#3f100d

#0d3f2a · #0d233f

#3f0d3c · #3c3f0d

Split-complementary

Open in tool →

#3f0d23 · #3f2a0d

#2a0d3f · #3f100d · #233f0d

Contrast

#0d3d40 as textRatioAAAA largeAAAFix
Aaon white
11.94:1passpasspassPasses AAA — no fix needed.
Aaon black
1.76:1failfailfail
  • AA: use #1d848c as the text (4.73:1)
  • AAA: use #24a8b2 as the text (7.32:1)
  • AA: or shift the background to #a1a1a1 (4.62:1)
  • AAA: or shift the background to #c7c7c7 (7.06:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0d3d40 as the background.

Brands using this color

Fonts for this mood

#0d3d40 reads as cool, vivid, dark. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0d3d40
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 #0d3d40 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0d3d40-a2b9be-df4e8a-1f262d-e9f1ee?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