Color

#42b3cd

#42b3cd
hex#42b3cd
rgbrgb(66, 179, 205)
hslhsl(191, 58%, 53%)
oklchoklch(0.714 0.106 216.1)
Closest name: Blue Bobbin (#52b4ca)Relative luminance 0.3781

Colors that go with #42b3cd

Charcoal, Denim and Midnight 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 →

#cd5b42

#42cda1 · #426ecd

#cd42b3 · #b3cd42

Split-complementary

Open in tool →

#cd426e · #cda142

#a142cd · #cd5b42 · #6ecd42

Contrast

#42b3cd as textRatioAAAA largeAAAFix
Aaon white
2.45:1failfailfail
  • AA: use #288195 as the text (4.5:1)
  • AAA: use #1d5e6d as the text (7.31:1)
  • AA: or shift the background to #3b3b3b (4.57:1)
  • AAA: or shift the background to #1a1a1a (7.1:1)
Aaon black
8.56:1passpasspassPasses 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 #42b3cd as the background.

Brands using this color

Palettes built around it

Fonts for this mood

#42b3cd reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #42b3cd
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 #42b3cd and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/42b3cd-a2b6be-df4e7a-1f252d-e9f1ef?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