Coastal
Open in tool →Sea-teal, sky and sand — bright without shouting; works for travel, wellness, and anything near water.
Color
#21a18c
#21a18c
hex
#21a18crgb
rgb(33, 161, 140)hsl
hsl(170, 66%, 38%)oklch
oklch(0.638 0.11 178.4)Closest name: Green Dynasty (#00988e)Relative luminance 0.2771
Colors that go with #21a18c
Charcoal, Blue and Copper 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.
Charcoal #36454f
neutralshippedCharcoal is the text near-black for #21a18c: softer than #000 and cool enough to feel like part of the same palette.
Blue #0000ff
shipped4 real palettes, including Unity's brand system and Kia's brand system put Blue beside #21a18c, as the supporting colour.
Copper #b87333
shippedDesigners have shipped Copper with #21a18c: 4 real palettes, including Clean Beauty and Wellness, as the accent.
Crimson #dc143c
shippedCrimson is paired with #21a18c in 6 real palettes, including Diner and DuckDuckGo's brand system, as the lead colour.
Denim #1560bd
shippedDesigners have shipped Denim with #21a18c: 5 real palettes, including Peacock and Intel's brand system, as the supporting colour.
Midnight Blue #191970
shipped7 real palettes, including Tide Pool and Fintech Trust put Midnight Blue beside #21a18c, as that palette's text colour.
Royal Blue #4169e1
shippedRoyal Blue is paired with #21a18c in 7 real palettes, including Khan Academy's brand system and Console Light, as the accent.
Deep Pink #ff1493
complementaryDeep Pink sits directly opposite #21a18c on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight.
Tints & shades
Harmonies
Contrast
| #21a18c as text | Ratio | AA | AA large | AAA | Fix |
|---|---|---|---|---|---|
Aaon white | 3.21:1 | fail | pass | fail | |
Aaon black | 6.54:1 | pass | pass | fail |
|
Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #21a18c as the background.
Brands using this color
No public brand in the corpus uses this exact color yet. Extract a brand to add one.
Palettes built around it
mcpConnect your agent — build around #21a18c
live endpointPoint 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.
endpoint
https://mcp.brandsweets.com/colors/mcpclaude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt
›analyze #21a18c and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link
tool url
/palettes/new/21a18c-a2bebd-d459a9-1f292d-e9f1ec?lock=0&style=vibrantWant the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.
Machine-readable: color.md