Color

#0300cc

#0300cc
hex#0300cc
rgbrgb(3, 0, 204)
hslhsl(241, 100%, 40%)
oklchoklch(0.383 0.264 264.4)
Closest name: mediumblue (#0000cd)Relative luminance 0.0438

Colors that go with #0300cc

Charcoal, Crimson and Cobalt 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 →

#c9cc00

#0063cc · #6900cc

#cc0300 · #00cc03

Split-complementary

Open in tool →

#cc6900 · #63cc00

#cc0063 · #c9cc00 · #00cc69

Contrast

#0300cc as textRatioAAAA largeAAAFix
Aaon white
11.2:1passpasspassPasses AAA — no fix needed.
Aaon black
1.88:1failfailfail
  • AA: use #6461ff as the text (4.7:1)
  • AAA: use #8c8aff as the text (7.19:1)
  • AA: or shift the background to #a6a6a6 (4.6:1)
  • AAA: or shift the background to #cfcfcf (7.19:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #0300cc as the background.

Brands using this color

Fonts for this mood

#0300cc reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #0300cc
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 #0300cc and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/0300cc-a19cc4-df9b4e-261f2d-e9edf1?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