Color

#3931d3

#3931d3
hex#3931d3
rgbrgb(57, 49, 211)
hslhsl(243, 65%, 51%)
oklchoklch(0.45 0.234 273.8)
Closest name: Lapis on Neptune (#1f22d2)Relative luminance 0.0777

Colors that go with #3931d3

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 →

#cbd331

#317ad3 · #8a31d3

#d33931 · #31d339

Split-complementary

Open in tool →

#d38a31 · #7ad331

#d3317a · #cbd331 · #31d38a

Contrast

#3931d3 as textRatioAAAA largeAAAFix
Aaon white
8.22:1passpasspassPasses AAA — no fix needed.
Aaon black
2.55:1failfailfail
  • AA: use #6d68df as the text (4.7:1)
  • AAA: use #928de7 as the text (7.19:1)
  • AA: or shift the background to #c2c2c2 (4.62:1)
  • AAA: or shift the background to #ededed (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 #3931d3 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

#3931d3 reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3931d3
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 #3931d3 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3931d3-a39cc4-dfa04e-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