Color

#3687ba

#3687ba
hex#3687ba
rgbrgb(54, 135, 186)
hslhsl(203, 55%, 47%)
oklchoklch(0.597 0.11 240.1)
Closest name: steelblue (#4682b4)Relative luminance 0.2166

Colors that go with #3687ba

Charcoal, Crimson and Royal 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 →

#ba6836

#36baaa · #3645ba

#ba3687 · #87ba36

Split-complementary

Open in tool →

#ba3645 · #baaa36

#aa36ba · #ba6836 · #45ba36

Contrast

#3687ba as textRatioAAAA largeAAAFix
Aaon white
3.94:1failpassfail
  • AA: use #317caa as the text (4.57:1)
  • AAA: use #255c7e as the text (7.21:1)
  • AA: or shift the background to #171717 (4.55:1)
Aaon black
5.33:1passpassfail
  • AAA: use #519dcd as the text (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 #3687ba 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

#3687ba reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3687ba
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 #3687ba and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3687ba-9cb0c4-df4e5d-1f222d-e9f1f0?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