Color

#428ccd

#428ccd
hex#428ccd
rgbrgb(66, 140, 205)
hslhsl(208, 58%, 53%)
oklchoklch(0.622 0.123 247.8)
Closest name: Blue Jay (#5588dd)Relative luminance 0.2432

Colors that go with #428ccd

Charcoal, Copper and Amber 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 →

#cd8342

#42cdc8 · #4246cd

#cd428c · #8ccd42

Split-complementary

Open in tool →

#cd4246 · #cdc842

#c842cd · #cd8342 · #46cd42

Contrast

#428ccd as textRatioAAAA largeAAAFix
Aaon white
3.58:1failpassfail
  • AA: use #317ab9 as the text (4.55:1)
  • AAA: use #245a89 as the text (7.24:1)
  • AA: or shift the background to #1f1f1f (4.6:1)
Aaon black
5.86:1passpassfail
  • AAA: use #5e9dd4 as the text (7.25:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #428ccd as the background.

Brands using this color

Fonts for this mood

#428ccd reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #428ccd
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 #428ccd and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/428ccd-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