Color

#3941b1

#3941b1
hex#3941b1
rgbrgb(57, 65, 177)
hslhsl(236, 51%, 46%)
oklchoklch(0.441 0.175 273.6)
Closest name: Cobalt Blue (#0047ab)Relative luminance 0.0782

Colors that go with #3941b1

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.

Tints & shades

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

Harmonies

Complementary

Open in tool →

#b1a939

#397db1 · #6d39b1

#b13941 · #41b139

Split-complementary

Open in tool →

#b16d39 · #7db139

#b1397d · #b1a939 · #39b16d

Contrast

#3941b1 as textRatioAAAA largeAAAFix
Aaon white
8.19:1passpasspassPasses AAA — no fix needed.
Aaon black
2.56:1failfailfail
  • AA: use #656ccd as the text (4.58:1)
  • AAA: use #8b91da as the text (7.16:1)
  • AA: or shift the background to #c2c2c2 (4.6:1)
  • AAA: or shift the background to #f0f0f0 (7.18:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3941b1 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

#3941b1 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3941b1
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 #3941b1 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3941b1-9e9cc4-df8f4e-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