Color

#3937a4

#3937a4
hex#3937a4
rgbrgb(57, 55, 164)
hslhsl(241, 50%, 43%)
oklchoklch(0.412 0.17 276.7)
Closest name: Bluebell (#333399)Relative luminance 0.0628

Colors that go with #3937a4

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 #3937a4

Tints & shades

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

Harmonies

Complementary

Open in tool →

#a3a437

#376ca4 · #6f37a4

#a43937 · #37a439

Split-complementary

Open in tool →

#a46f37 · #6ca437

#a4376c · #a3a437 · #37a46f

Contrast

#3937a4 as textRatioAAAA largeAAAFix
Aaon white
9.31:1passpasspassPasses AAA — no fix needed.
Aaon black
2.26:1failfailfail
  • AA: use #6b6acd as the text (4.57:1)
  • AAA: use #9190da as the text (7.21:1)
  • AA: or shift the background to #b5b5b5 (4.54:1)
  • AAA: or shift the background to #e0e0e0 (7.05:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3937a4 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

#3937a4 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3937a4
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 #3937a4 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3937a4-a19cc4-df9b4e-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