SmoothInvoice is a free, browser-based invoicing tool for freelancers and small businesses in Germany. It handles the small-business VAT exemption (§ 19 UStG) as well as 19 % and 7 % VAT, reverse charge for EU customers and exports to non-EU countries. Every open invoice gets an EPC payment QR code, so clients pay by scanning it with their banking app. Invoices can be exported as XRechnung 3.0, validated against the official KoSIT validator. No account and no server: invoices, customers and settings stay in the browser on the user's own device. Interface in German.