Color

#3739ae

#3739ae
hex#3739ae
rgbrgb(55, 57, 174)
hslhsl(239, 52%, 45%)
oklchoklch(0.423 0.181 274.7)
Closest name: Bluebell (#333399)Relative luminance 0.0679

Colors that go with #3739ae

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 →

#aeac37

#3775ae · #7137ae

#ae3739 · #39ae37

Split-complementary

Open in tool →

#ae7137 · #75ae37

#ae3775 · #aeac37 · #37ae71

Contrast

#3739ae as textRatioAAAA largeAAAFix
Aaon white
8.9:1passpasspassPasses AAA — no fix needed.
Aaon black
2.36:1failfailfail
  • AA: use #686acf as the text (4.55:1)
  • AAA: use #8f90dc as the text (7.19:1)
  • AA: or shift the background to #bababa (4.59:1)
  • AAA: or shift the background to #e6e6e6 (7.13:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3739ae 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

#3739ae reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3739ae
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 #3739ae and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3739ae-a09cc4-df964e-251f2d-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