Color

#3d55db

#3d55db
hex#3d55db
rgbrgb(61, 85, 219)
hslhsl(231, 69%, 55%)
oklchoklch(0.516 0.205 269.8)
Closest name: Arcane Brew (#5260e1)Relative luminance 0.126

Colors that go with #3d55db

Charcoal, Sea Green 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 →

#dbc43d

#3da4db · #743ddb

#db3d55 · #55db3d

Split-complementary

Open in tool →

#db743d · #a4db3d

#db3da4 · #dbc43d · #3ddb74

Contrast

#3d55db as textRatioAAAA largeAAAFix
Aaon white
5.96:1passpassfail
  • AAA: use #2c46d8 as the text (7.06:1)
Aaon black
3.52:1failpassfail
  • AA: use #576ce0 as the text (4.63:1)
  • AAA: use #8291e8 as the text (7.16:1)
  • AA: or shift the background to #e0e0e0 (4.52:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3d55db as the background.

Brands using this color

Fonts for this mood

#3d55db reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3d55db
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 #3d55db and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3d55db-9c9ec4-df834e-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