Validate
Have an invoice to check?
Check a document with a free validator.
Other formats: XRechnung or ZUGFeRD / Factur-X.
Learn
Learn e-invoicing
Understand the standards. Check a document. Fix the errors.
Look up a rule
Got a rule code?
Find what failed, why it happened and how to fix it.
Get started
New to e-invoicing?
Understand the formats, standards and rules, and how they fit together.
- PeppolUsage rulesPeppol BIS Billing 3
- EN 16931Core requirementsThe European standard
- UBL 2.1Document syntaxHow the invoice is written
Explore by task
View all articlesGuided paths
Guided path
Your first Peppol invoice
Know what a Peppol BIS Billing 3 invoice contains, check one, fix a finding and validate from your own code.
5 stepsPeppol BIS Billing 3EN 16931UBL
Guided path
Get started with XRechnung
Know which XRechnung you have, check it in UBL or CII, read the findings and call the same checks from code.
5 stepsXRechnungUBL or CIIGermany
Understand
Understand the formats and standards
Start with the basics, then go deeper on the format you work with.
- E-invoicing basicsGuideSyntax, EN 16931 and usage rules, and how Peppol, XRechnung and ZUGFeRD differ.
- How Peppol invoice validation actually worksArticleWhat each validation layer checks, from well-formed XML to the Peppol rules.
- XRechnung guideGuideVersions, variants, UBL and CII, and what the XRechnung checks cover.
- ZUGFeRD / Factur-X guideGuideProfiles, the PDF with its embedded XML, and what is and is not checked.
Validate
Validate a document
Each validator checks one format. Choose the one your document declares; the viewer shows what a UBL invoice says without judging it.
- Peppol invoice validatorToolA UBL invoice or credit note, checked against EN 16931 and Peppol BIS Billing 3.
- XRechnung validatorToolAn XRechnung in UBL or CII, checked against the official XRechnung 3.0.2 rules.
- ZUGFeRD / Factur-X validatorToolA hybrid PDF or its CII XML: the PDF/A, the embedded invoice and the profile rules.
- XML invoice viewerToolA UBL or Peppol invoice as a readable document, to see what the XML says.
Fix
Fix a validation error
Read the rule code in your result, then look it up. The annotated example walks through one mistake, a line total that does not add up (BR-CO-10), and its correction.
- Understanding EN 16931 validation errorsArticleHow to read rule IDs, business terms and VAT rule families in a finding.
- Rule referenceReferenceLook up a rule code: what failed, why, and a tested fix.
- A broken invoice, and the fixExampleThe annotated Peppol example with a totals mistake and its correction.
Integrate
Integrate validation
The same checks the free tools run are available through the Ironfang Finance API.
Bring validation into your application
Use Ironfang Finance to run checks in your own workflow and handle the findings in code.