Color

#3bb1b5

#3bb1b5
hex#3bb1b5
rgbrgb(59, 177, 181)
hslhsl(182, 51%, 47%)
oklchoklch(0.698 0.102 198.3)
Closest name: lightseagreen (#20b2aa)Relative luminance 0.3571

Colors that go with #3bb1b5

Charcoal, Denim and Dodger 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 →

#b53f3b

#3bb57c · #3b74b5

#b53bb1 · #b1b53b

Split-complementary

Open in tool →

#b53b74 · #b57c3b

#7c3bb5 · #b53f3b · #74b53b

Contrast

#3bb1b5 as textRatioAAAA largeAAAFix
Aaon white
2.58:1failfailfail
  • AA: use #2a8083 as the text (4.65:1)
  • AAA: use #206264 as the text (7.02:1)
  • AA: or shift the background to #383838 (4.55:1)
  • AAA: or shift the background to #141414 (7.14:1)
Aaon black
8.14:1passpasspassPasses 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 #3bb1b5 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

#3bb1b5 reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3bb1b5
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 #3bb1b5 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3bb1b5-a2babe-d45990-1f272d-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