Color

#21cbde

#21cbde
hex#21cbde
rgbrgb(33, 203, 222)
hslhsl(186, 74%, 50%)
oklchoklch(0.772 0.128 207.2)
Closest name: darkturquoise (#00ced1)Relative luminance 0.4831

Tints & shades

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

Harmonies

Complementary

Open in tool →

#de3421

#21de92 · #216dde

#de21cb · #cbde21

Split-complementary

Open in tool →

#de216d · #de9221

#9221de · #de3421 · #6dde21

Contrast

#21cbde as textRatioAAAA largeAAAFix
Aaon white
1.97:1failfailfail
  • AA: use #15828e as the text (4.55:1)
  • AAA: use #10616a as the text (7.14:1)
  • AA: or shift the background to #474747 (4.72:1)
  • AAA: or shift the background to #2b2b2b (7.19:1)
Aaon black
10.66:1passpasspassPasses 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 #21cbde 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

#21cbde reads as cool, vivid, technical. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #21cbde
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 #21cbde and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/21cbde-a2b8be-df4e86-1f262d-e9f1ee?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