Color

#3789fb

#3789fb
hex#3789fb
rgbrgb(55, 137, 251)
hslhsl(215, 96%, 60%)
oklchoklch(0.64 0.188 257.6)
Closest name: dodgerblue (#1e90ff)Relative luminance 0.2567

Colors that go with #3789fb

Charcoal, Red 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 →

#fba937

#37ebfb · #4737fb

#fb3789 · #89fb37

Split-complementary

Open in tool →

#fb4737 · #ebfb37

#fb37eb · #fba937 · #37fb47

Contrast

#3789fb as textRatioAAAA largeAAAFix
Aaon white
3.42:1failpassfail
  • AA: use #0a6efa as the text (4.54:1)
  • AAA: use #0451be as the text (7.18:1)
  • AA: or shift the background to #242424 (4.53:1)
Aaon black
6.13:1passpassfail
  • AAA: use #5097fb as the text (7.16:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3789fb as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#3789fb reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3789fb
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 #3789fb and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3789fb-9ca8c4-df5d4e-201f2d-e9f0f1?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