Color

#3971db

#3971db
hex#3971db
rgbrgb(57, 113, 219)
hslhsl(219, 69%, 54%)
oklchoklch(0.568 0.173 261.7)
Closest name: royalblue (#4169e1)Relative luminance 0.1779

Tints & shades

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

Harmonies

Complementary

Open in tool →

#dba239

#39c2db · #5139db

#db3971 · #71db39

Split-complementary

Open in tool →

#db5139 · #c2db39

#db39c2 · #dba239 · #39db51

Contrast

#3971db as textRatioAAAA largeAAAFix
Aaon white
4.61:1passpassfail
  • AAA: use #2053b1 as the text (7.16:1)
Aaon black
4.56:1passpassfail
  • AAA: use #6c96e4 as the text (7.12:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3971db 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

#3971db reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3971db
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — generate_palette, check_contrast, analyze_color — read-only, no key. Every palette it proposes comes with a /palettes/new/… link: open it, lock what you like, paste the link back.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #3971db and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3971db-9ca5c4-df664e-211f2d-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