Color

#40b571

#40b571
hex#40b571
rgbrgb(64, 181, 113)
hslhsl(145, 48%, 48%)
oklchoklch(0.69 0.145 154.2)
Closest name: mediumseagreen (#3cb371)Relative luminance 0.3533

Colors that go with #40b571

Charcoal, Mustard Yellow and Royal 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 →

#b54084

#49b540 · #40b5ab

#7140b5 · #b57140

Split-complementary

Open in tool →

#ab40b5 · #b54049

#4049b5 · #b54084 · #b5ab40

Contrast

#40b571 as textRatioAAAA largeAAAFix
Aaon white
2.6:1failfailfail
  • AA: use #2e8452 as the text (4.63:1)
  • AAA: use #22623d as the text (7.29:1)
  • AA: or shift the background to #383838 (4.5:1)
  • AAA: or shift the background to #141414 (7.08:1)
Aaon black
8.07:1passpasspassPasses 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 #40b571 as the background.

Brands using this color

mcpConnect your agent — build around #40b571
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 #40b571 and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/40b571-a2beb1-cc59d4-1f2d2b-eaf1e9?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