Color

#40b57e

#40b57e
hex#40b57e
rgbrgb(64, 181, 126)
hslhsl(152, 48%, 48%)
oklchoklch(0.693 0.133 159.2)
Closest name: mediumseagreen (#3cb371)Relative luminance 0.3564

Colors that go with #40b57e

Charcoal, Blue and Cornflower 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 →

#b54076

#40b544 · #40b1b5

#7e40b5 · #b57e40

Split-complementary

Open in tool →

#b540b1 · #b54440

#4440b5 · #b54076 · #b1b540

Contrast

#40b57e as textRatioAAAA largeAAAFix
Aaon white
2.58:1failfailfail
  • AA: use #2e845c as the text (4.59:1)
  • AAA: use #226244 as the text (7.24:1)
  • AA: or shift the background to #383838 (4.54:1)
  • AAA: or shift the background to #141414 (7.13:1)
Aaon black
8.13:1passpasspassPasses 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 #40b57e as the background.

Brands using this color

Palettes built around it

mcpConnect your agent — build around #40b57e
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 #40b57e and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/40b57e-a2beb4-d459ce-1f2d2d-e9f1ea?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