Color

#283d57

#283d57
hex#283d57
rgbrgb(40, 61, 87)
hslhsl(213, 37%, 25%)
oklchoklch(0.355 0.053 254.3)
Closest name: Capital Blue (#1a4157)Relative luminance 0.0448

Colors that go with #283d57

Dark Olive Green, Sea Green and Teal 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 →

#574228

#285557 · #2b2857

#57283d · #3d5728

Split-complementary

Open in tool →

#572b28 · #555728

#572855 · #574228 · #28572b

Contrast

#283d57 as textRatioAAAA largeAAAFix
Aaon white
11.08:1passpasspassPasses AAA — no fix needed.
Aaon black
1.9:1failfailfail
  • AA: use #4f78ab as the text (4.61:1)
  • AAA: use #7798c0 as the text (7.04:1)
  • AA: or shift the background to #a6a6a6 (4.55:1)
  • AAA: or shift the background to #cfcfcf (7.11:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #283d57 as the background.

Brands using this color

Fonts for this mood

#283d57 reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #283d57
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 #283d57 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/283d57-9ca9c4-df584e-1f202d-e9f0f1?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