# einvoicechecker.com

> Free online viewer and validator for European e-invoices (XRechnung, ZUGFeRD, Factur-X, Peppol BIS 3.0, UBL, CII, KSeF FA(3)), plus a REST API and a remote MCP server with the same engine. Validation uses the official KoSIT (XRechnung 3.0.2), OpenPeppol (BIS Billing 3.0.20) and Polish FA(3) rule sets. Files are processed in memory and never stored.

## For AI agents
- MCP server (Streamable HTTP): https://einvoicechecker.com/v1/mcp — docs https://einvoicechecker.com/mcp/
- Server card: https://einvoicechecker.com/.well-known/mcp/server-card.json
- REST API docs: https://einvoicechecker.com/developers/ (POST /v1/detect, /v1/parse, /v1/validate, /v1/render, /v1/inspect; API key via Authorization: Bearer)
- Pricing: https://einvoicechecker.com/pricing/ (free 100 requests/month, Starter €24, Pro €49, Business €149)

## Tools (web)
- https://einvoicechecker.com/ open and check any EU e-invoice
- https://einvoicechecker.com/xrechnung-viewer/
- https://einvoicechecker.com/zugferd-validator/
- https://einvoicechecker.com/factur-x-validator/
- https://einvoicechecker.com/peppol-validator/
- https://einvoicechecker.com/ubl-invoice-viewer/
- https://einvoicechecker.com/ksef-validator/
- German: https://einvoicechecker.com/de/ · French: https://einvoicechecker.com/fr/ · Polish: https://einvoicechecker.com/pl/ · Dutch: https://einvoicechecker.com/nl/

## Auto-fix
- POST https://einvoicechecker.com/v1/fix : corrects validation errors of EN 16931 invoices (XRechnung, Peppol, ZUGFeRD/Factur-X XML) deterministically and returns the corrected XML plus a change list. ?totals=1 recalculates totals and VAT from the lines, ?dry_run=1 only reports. Missing data (Leitweg-ID, seller contact, endpoint ids, payment terms) via JSON {"xml":…, "values":{…}}. MCP tool: fix_invoice.

## Validation rule catalogue
- https://einvoicechecker.com/rules/ : every EN 16931, Peppol BIS 3.0 and XRechnung business rule (BR-xx, BR-CO-xx, BR-DE-xx, PEPPOL-EN16931-Rxxx) with official text, XPath test, cause and fix. One page per rule, e.g. https://einvoicechecker.com/rules/br-de-15/ ; German: https://einvoicechecker.com/de/regeln/
- Validation responses (API and MCP) include a `help` URL per failed rule pointing to these pages.

## Legal
- https://einvoicechecker.com/about/ · https://einvoicechecker.com/privacy/ · https://einvoicechecker.com/terms/ · https://einvoicechecker.com/contact/