Color

#428a5a

#428a5a
hex#428a5a
rgbrgb(66, 138, 90)
hslhsl(140, 35%, 40%)
oklchoklch(0.574 0.104 152.7)
Closest name: seagreen (#2e8b57)Relative luminance 0.2007

Colors that go with #428a5a

Charcoal, Royal Blue and Rust 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 →

#8a4272

#4e8a42 · #428a7e

#5a428a · #8a5a42

Split-complementary

Open in tool →

#7e428a · #8a424e

#424e8a · #8a4272 · #8a7e42

Contrast

#428a5a as textRatioAAAA largeAAAFix
Aaon white
4.19:1failpassfail
  • AA: use #3f8356 as the text (4.57:1)
  • AAA: use #2e603f as the text (7.34:1)
  • AA: or shift the background to #0f0f0f (4.58:1)
Aaon black
5.01:1passpassfail
  • AAA: use #51a96e as the text (7.25:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #428a5a as the background.

Brands using this color

No public brand in the corpus uses this exact color yet. Extract a brand to add one.

mcpConnect your agent — build around #428a5a
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 #428a5a and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/428a5a-a2beaf-c259d4-1f2d2a-ebf1e9?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