Color

#39b5ef

#39b5ef
hex#39b5ef
rgbrgb(57, 181, 239)
hslhsl(199, 85%, 58%)
oklchoklch(0.731 0.135 233.7)
Closest name: Blue Bikini (#00bbee)Relative luminance 0.4015

Tints & shades

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

Harmonies

Complementary

Open in tool →

#ef7339

#39efce · #395aef

#ef39b5 · #b5ef39

Split-complementary

Open in tool →

#ef395a · #efce39

#ce39ef · #ef7339 · #5aef39

Contrast

#39b5ef as textRatioAAAA largeAAAFix
Aaon white
2.33:1failfailfail
  • AA: use #0e7caf as the text (4.65:1)
  • AAA: use #0b5e84 as the text (7.12:1)
  • AA: or shift the background to #3d3d3d (4.67:1)
  • AAA: or shift the background to #1f1f1f (7.09:1)
Aaon black
9.03:1passpasspassPasses AAA — no fix needed.

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #39b5ef as the background.

Brands using this color

Fonts for this mood

#39b5ef reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #39b5ef
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 #39b5ef and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/39b5ef-9cb3c4-df4e66-1f232d-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