Playground

Break an invoice. Fix it. Generate the XML.

This page runs @attestwire/en16931 0.5.0 — the same MIT engine behind the hosted API — compiled for the browser. Your invoice is validated on this machine. There is no API key, no upload and no request: close the tab and nothing was sent anywhere.

The sample is one field short of conformant

It is a complete XRechnung invoice with buyerReference removed, which is the field BR-DE-15 exists to require. Press Validate to see what the engine says, Fix it to put the field back, then Generate XML.

Invoice JSON

{
  "profile": "xrechnung-ubl",
  "invoiceNumber": "2026-000142",
  "issueDate": "2026-08-09",
  "currency": "EUR",
  "invoiceTypeCode": "380",
  "seller": {
    "name": "Acme GmbH",
    "vatId": "DE123456789",
    "address": {
      "line1": "Chausseestr. 1",
      "city": "Berlin",
      "postalCode": "10115",
      "countryCode": "DE"
    },
    "electronicAddress": {
      "schemeId": "0204",
      "value": "04011000-1234512345-06"
    },
    "contact": {
      "name": "Buchhaltung",
      "phone": "+49 30 1234567",
      "email": "rechnungen@acme.example"
    }
  },
  "buyer": {
    "name": "Stadt Bonn",
    "vatId": "DE987654321",
    "address": {
      "line1": "Berliner Platz 2",
      "city": "Bonn",
      "postalCode": "53111",
      "countryCode": "DE"
    },
    "electronicAddress": {
      "schemeId": "0204",
      "value": "04011000-1234512345-06"
    }
  },
  "lines": [
    {
      "id": "1",
      "description": "Consulting, August 2026",
      "quantity": 10,
      "unitCode": "HUR",
      "unitPrice": 150,
      "vatCategory": "S",
      "vatRate": 19
    }
  ],
  "payment": {
    "meansCode": "58",
    "iban": "DE02120300000000202051",
    "accountName": "Acme GmbH"
  },
  "paymentTerms": "30 days net"
}

Output

The buttons need JavaScript, because the engine runs here rather than on a server. Everything below is what the build got when it ran this exact invoice.
Install the library

The output choice sets the invoice's own profile field before generating — that field is what selects the rule sets and the specification identifier.

valid: false — 1 error.

BR-DE-15 BT-10

XRechnung requires a buyer reference (BT-10). For German public-sector buyers this is the Leitweg-ID; business buyers may supply any reference, but the field must be present.

Fix: Ask your client for their Leitweg-ID (public sector) or an order/customer reference, and set buyerReference.

Read BR-DE-15 →

Generated XML

valid: true here means the document data passed every rule Attestwire implements. It is not a promise that a receiver, an access point or a national overlay will accept the document. Read the exact limits →

You got a document. Now put it in your system.

Run it in your own code. The package is MIT, has zero runtime dependencies and needs no account.

JavaScript or TypeScript

npm install @attestwire/en16931

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