Documentation
Everything you need to generate and validate compliant German e-invoices — XRechnung, ZUGFeRD, and EN 16931 — with one API.
What InvoiceSpec supports today
InvoiceSpec focuses on generating and validating compliant German e-invoices. The table below states the current scope plainly so you can tell at a glance whether it fits your use case.
| Operation | Status | Details |
|---|---|---|
| Generate | Supported | XRechnung, EN 16931, and ZUGFeRD XML output. |
| Validate | Supported | XRechnung, EN 16931, and ZUGFeRD validation. |
| Convert | Not currently supported | Cross-format conversion is not currently supported. |
| Transform | Not currently supported | In-place document transformation is not currently supported. |
| Extract | Not currently supported | Structured data extraction from XML is not currently supported. |
| Render | Not currently supported | Human-readable PDF/HTML rendering is not currently supported. |
| Embed | Not currently supported | Embedding XML inside a PDF (e.g. ZUGFeRD PDF-A3) is not currently supported. |
Sections
Getting Started
Prerequisites, registration, acquiring an API key, your first request, and how to read the response.
Read moreAPI Reference
Generate and validate XRechnung, EN 16931, and ZUGFeRD with endpoint-specific schemas, examples, and recovery guidance.
Read moreInvoice JSON Schema
The invoice request contract — field meaning, structure, requirement status, constraints, and valid examples.
Read moreError Codes
Every API error code in one place — status, code, description, and remediation action — with links back to the endpoint where each appears.
Read moreRate Limits
Per-plan request rate, burst, and concurrency allowances, the shared per-user pool, and how effective limits are resolved from your current subscription.
Read moreGlossary
Plain-language definitions of e-invoicing terms used across the docs — EN 16931, XRechnung, ZUGFeRD, CII, UBL, BT/BG/BR, Schematron, and more.
Read moreChangelog
Dated entries for spec-version bumps, new endpoints, and breaking changes — starting from the documentation competitive uplift and growing forward with each release.
Read more
Quick start
New to InvoiceSpec? Start with the getting started guide, then check the API reference and the invoice JSON schema.
Generate your first compliant invoice in under 5 minutes.