Yes. Custom branding — colors, logo, and brand name — is completely free for any website, blog, or app, with no account required. The only paid option is removing the "Powered by CalculatorApp.me" attribution badge, available on the Pro plan.

Pick a calculator, customize the width, theme, and colors in the live preview, then copy the generated <iframe> code and paste it into your page's HTML. No API key, backend, or JavaScript setup required.

Yes. You can set a custom accent color, switch between light and dark theme, and choose a compact or standard layout so the widget blends into your existing page design.

Yes. Every embed is responsive by default — set width to 100% (the default) and it will resize to fit any screen, from mobile phones to desktop.

Yes, there's no limit. Generate a separate embed code for each calculator you want to include and place the <iframe> tags anywhere in your page's HTML.