Color

#283dc3

#283dc3
hex#283dc3
rgbrgb(40, 61, 195)
hslhsl(232, 66%, 46%)
oklchoklch(0.442 0.207 268.6)
Closest name: Cobalt Blue (#0047ab)Relative luminance 0.0773

Colors that go with #283dc3

Charcoal, Sea Green 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 →

#c3ae28

#288ac3 · #6128c3

#c3283d · #3dc328

Split-complementary

Open in tool →

#c36128 · #8ac328

#c3288a · #c3ae28 · #28c361

Contrast

#283dc3 as textRatioAAAA largeAAAFix
Aaon white
8.25:1passpasspassPasses AAA — no fix needed.
Aaon black
2.55:1failfailfail
  • AA: use #5a6bdd as the text (4.58:1)
  • AAA: use #8491e6 as the text (7.17:1)
  • AA: or shift the background to #c2c2c2 (4.63:1)
  • AAA: or shift the background to #ededed (7.05:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #283dc3 as the background.

Brands using this color

Fonts for this mood

#283dc3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #283dc3
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 #283dc3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/283dc3-9c9dc4-df864e-231f2d-e9eef1?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