Color

#1d2f3f

#1d2f3f
hex#1d2f3f
rgbrgb(29, 47, 63)
hslhsl(208, 37%, 18%)
oklchoklch(0.297 0.038 246.3)
Closest name: Blue Whale (#1e3442)Relative luminance 0.0265

Colors that go with #1d2f3f

Dark Olive Green, Sienna and Slate 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 →

#3f2d1d

#1d3f3e · #1d1e3f

#3f1d2f · #2f3f1d

Split-complementary

Open in tool →

#3f1d1e · #3f3e1d

#3e1d3f · #3f2d1d · #1e3f1d

Contrast

#1d2f3f as textRatioAAAA largeAAAFix
Aaon white
13.72:1passpasspassPasses AAA — no fix needed.
Aaon black
1.53:1failfailfail
  • AA: use #4c7ba4 as the text (4.68:1)
  • AAA: use #739cbf as the text (7.24:1)
  • AA: or shift the background to #949494 (4.52:1)
  • AAA: or shift the background to #bababa (7.07:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1d2f3f as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#1d2f3f reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1d2f3f
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 #1d2f3f and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1d2f3f-9cadc4-df4e51-1f212d-e9f1f1?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