Color

#3b5ce3

#3b5ce3
hex#3b5ce3
rgbrgb(59, 92, 227)
hslhsl(228, 75%, 56%)
oklchoklch(0.534 0.208 268)
Closest name: Arcane Brew (#5260e1)Relative luminance 0.1413

Colors that go with #3b5ce3

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 →

#e3c13b

#3bb0e3 · #6d3be3

#e33b5c · #5ce33b

Split-complementary

Open in tool →

#e36d3b · #b0e33b

#e33bb0 · #e3c13b · #3be36d

Contrast

#3b5ce3 as textRatioAAAA largeAAAFix
Aaon white
5.49:1passpassfail
  • AAA: use #1f45db as the text (7.16:1)
Aaon black
3.83:1failpassfail
  • AA: use #4c6be6 as the text (4.55:1)
  • AAA: use #7990ec as the text (7.01:1)
  • AA: or shift the background to #ebebeb (4.6:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3b5ce3 as the background.

Brands using this color

Fonts for this mood

#3b5ce3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3b5ce3
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 #3b5ce3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3b5ce3-9c9fc4-df7c4e-231f2d-e9eff1?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