Color

#303cc0

#303cc0
hex#303cc0
rgbrgb(48, 60, 192)
hslhsl(235, 60%, 47%)
oklchoklch(0.441 0.203 270.9)
Closest name: Cobalt Blue (#0047ab)Relative luminance 0.0767

Colors that go with #303cc0

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 →

#c0b430

#3084c0 · #6c30c0

#c0303c · #3cc030

Split-complementary

Open in tool →

#c06c30 · #84c030

#c03084 · #c0b430 · #30c06c

Contrast

#303cc0 as textRatioAAAA largeAAAFix
Aaon white
8.29:1passpasspassPasses AAA — no fix needed.
Aaon black
2.53:1failfailfail
  • AA: use #606ad7 as the text (4.54:1)
  • AAA: use #8990e1 as the text (7.14:1)
  • AA: or shift the background to #bfbfbf (4.51:1)
  • AAA: or shift the background to #ededed (7.08:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #303cc0 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

#303cc0 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #303cc0
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 #303cc0 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/303cc0-9e9cc4-df8d4e-241f2d-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