Color

#1d3a4e

#1d3a4e
hex#1d3a4e
rgbrgb(29, 58, 78)
hslhsl(204, 46%, 21%)
oklchoklch(0.335 0.05 240.6)
Closest name: Astral Nomad (#203943)Relative luminance 0.0384

Colors that go with #1d3a4e

Royal Blue, Teal and Sienna 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 →

#4e311d

#1d4e49 · #1d224e

#4e1d3a · #3a4e1d

Split-complementary

Open in tool →

#4e1d22 · #4e491d

#491d4e · #4e311d · #224e1d

Contrast

#1d3a4e as textRatioAAAA largeAAAFix
Aaon white
11.88:1passpasspassPasses AAA — no fix needed.
Aaon black
1.77:1failfailfail
  • AA: use #3d7ba4 as the text (4.57:1)
  • AAA: use #639ec5 as the text (7.23:1)
  • AA: or shift the background to #a1a1a1 (4.6:1)
  • AAA: or shift the background to #c7c7c7 (7.03:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #1d3a4e as the background.

Brands using this color

Fonts for this mood

#1d3a4e reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #1d3a4e
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 #1d3a4e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/1d3a4e-9cafc4-df4e5a-1f222d-e9f1f0?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