Color

#303ba1

#303ba1
hex#303ba1
rgbrgb(48, 59, 161)
hslhsl(234, 54%, 41%)
oklchoklch(0.411 0.163 272.2)
Closest name: Bluebell (#333399)Relative luminance 0.0633

Colors that go with #303ba1

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.

Real palettes that use #303ba1

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#a19630

#3074a1 · #5d30a1

#a1303b · #3ba130

Split-complementary

Open in tool →

#a15d30 · #74a130

#a13074 · #a19630 · #30a15d

Contrast

#303ba1 as textRatioAAAA largeAAAFix
Aaon white
9.27:1passpasspassPasses AAA — no fix needed.
Aaon black
2.27:1failfailfail
  • AA: use #626dd0 as the text (4.62:1)
  • AAA: use #8991dc as the text (7.15:1)
  • AA: or shift the background to #b5b5b5 (4.52:1)
  • AAA: or shift the background to #e0e0e0 (7.02:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #303ba1 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

#303ba1 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #303ba1
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 #303ba1 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/303ba1-9d9cc4-df8a4e-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