Color

#283a57

#283a57
hex#283a57
rgbrgb(40, 58, 87)
hslhsl(217, 37%, 25%)
oklchoklch(0.347 0.056 259.6)
Closest name: Capital Blue (#1a4157)Relative luminance 0.0417

Colors that go with #283a57

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 →

#574528

#285257 · #2e2857

#57283a · #3a5728

Split-complementary

Open in tool →

#572e28 · #525728

#572852 · #574528 · #28572e

Contrast

#283a57 as textRatioAAAA largeAAAFix
Aaon white
11.46:1passpasspassPasses AAA — no fix needed.
Aaon black
1.83:1failfailfail
  • AA: use #5477b0 as the text (4.64:1)
  • AAA: use #7e99c4 as the text (7.24:1)
  • AA: or shift the background to #a3a3a3 (4.54:1)
  • AAA: or shift the background to #cccccc (7.13:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #283a57 as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

Fonts for this mood

#283a57 reads as cool, dark, luxury. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #283a57
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 #283a57 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/283a57-9ca7c4-df624e-201f2d-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