Founder and developer of NormAPI, a REST API for German e-invoices (XRechnung, ZUGFeRD).

Dmytro Yalanskyi • Peerlist

NormAPI is a REST API for German e-invoices.POST JSON to /v1/invoices and get back XRechnung (UBL or CII) or a ZUGFeRD/Factur-X PDF. Every invoice is validated against the official KoSIT rule set before it is returned.POST an XML or PDF to /v1/validate and get the verdict, each finding with rule code, severity and location, and the rule-set version that produced it. Business-rule findings come with a plain-language explanation of cause and fix, in English or German.German businesses must accept e-invoices since 2025, and issuing them becomes mandatory in 2027 and 2028. KoSIT updates the rules about twice a year; NormAPI follows each release, so your integration stays the same.Free: the browser validator (no sign-up) and the validation endpoint. A free account includes 25 generated invoices a month; Starter is €49/month for 500, Business €149/month for 2,500. Invoice content is processed in the EU and not stored. OpenAPI spec, Postman collection and an npm client are available.