No61.app - Build & stress-test color palettes

No61 is a color palette builder for designers and developers who want to see how their colors actually perform in a real UI — not just as swatches. Preview your palette live on 40+ real components: dashboards, pricing tables, e-commerce layouts, charts, chat widgets and more. WCAG 2 and APCA contrast checking built in. Export to Tailwind CSS, SCSS, plain CSS or Figma.