Color

#31b5fc

#31b5fc
hex#31b5fc
rgbrgb(49, 181, 252)
hslhsl(201, 97%, 59%)
oklchoklch(0.736 0.149 238.3)
Closest name: deepskyblue (#00bfff)Relative luminance 0.4073

Colors that go with #31b5fc

Charcoal, Dark Orange 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 →

#fc7831

#31fcdd · #314ffc

#fc31b5 · #b5fc31

Split-complementary

Open in tool →

#fc314f · #fcdd31

#dd31fc · #fc7831 · #4ffc31

Contrast

#31b5fc as textRatioAAAA largeAAAFix
Aaon white
2.3:1failfailfail
  • AA: use #037aba as the text (4.67:1)
  • AAA: use #025c8d as the text (7.2:1)
  • AA: or shift the background to #404040 (4.52:1)
  • AAA: or shift the background to #212121 (7.01:1)
Aaon black
9.15:1passpasspassPasses 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 #31b5fc as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#31b5fc reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #31b5fc
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 #31b5fc and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/31b5fc-9cb1c4-df4e62-1f222d-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