Free UBL 2.1 Invoice Validator

UBL (Universal Business Language) 2.1 is an OASIS open standard XML format for business documents. It's the foundation for Peppol BIS and many national e-invoicing implementations, supporting invoices, orders, and 60+ document types.

Checking is free.Finished e-invoice: €1.90.First file every 30 days free.No sign-up.

No file yet? Fill in the form

Your file is used only to check and fix your invoice and to deliver your result. Results are kept so you can download a verified file again for 90 days; validation logs are deleted after 90 days. You can request deletion at any time.

What this check settles

Details are missingYou supply them, we enter them and check again. Amounts, line items and taxes stay unchanged.
The export is structurally brokenYou get the error report for your ERP support: rule, position in the file, expected structure. Free.
The file passes the checkDownload only then, with check protocol, timestamp and checksum. Publicly verifiable.

What we check for UBL

UBL 2.1 XML schema validation
EN 16931 business rules
Namespace and element structure
Code list validation
Party and address structure
Tax calculation rules
Invoice line consistency

Common UBL rejections

UBL-CR-001Invalid XML syntaxUBL-CR-002Invalid namespaceUBL-SR-01Namespace declaration requiredUBL-SR-06Invalid date formatUBL-CR-005Empty element not allowedAll error codes, explained →

Where this check runs

Invoice NavigatorSchema + business rules in one check. Identifies namespace issues, element structure problems, and EN 16931 violations.
Access pointPeppol Access Points validate UBL but only for Peppol-specific rules. Generic UBL validation not included.
ERP built-inERP systems generate UBL but rarely validate against full schema. Structural issues may only surface at recipient.

UBL at a glance

Full NameUniversal Business Language
Version2.1
Maintained ByOASIS
Document Types65+
Used ByPeppol, XRechnung

Countries using UBL

European UnionAustraliaNew ZealandSingapore

UBL FAQ

What is UBL 2.1?
UBL (Universal Business Language) 2.1 is an open XML standard from OASIS. It defines 65 business document types, including the invoice and the credit note. Later UBL versions exist, but EN 16931 and Peppol BIS are built on UBL 2.1.
Is UBL the same as Peppol?
No. UBL is the document format; Peppol is the network. Peppol BIS Billing is built on UBL 2.1 with additional business rules.
Should I use UBL or CII for EN 16931?
Both are valid syntaxes for EN 16931. UBL is more common internationally (Peppol uses it), while CII is used in hybrid formats like ZUGFeRD and Factur-X.
What are the cbc: and cac: prefixes?
They are the conventional prefixes for two UBL namespaces: cbc (CommonBasicComponents) holds simple values, cac (CommonAggregateComponents) holds composite structures such as parties and addresses.
Which standards are built on UBL?
Peppol BIS Billing 3.0, XRechnung (UBL variant), A-NZ Peppol (Australia and New Zealand) and Singapore's InvoiceNow all use UBL 2.1 as their syntax. A generic UBL check covers the schema and EN 16931; format-specific rules need the format's own check.
Is checking free?
Checking is free. The first verified download every 30 days is free. After that €1.90 per invoice, or €9 a month for all of them. Checking needs no account. You only pay when a file has passed the check and you download it.
Do you fix my invoice automatically?
No. We never change amounts, line items or taxes. Where mandatory details are missing, you supply them, we enter them and check the file again. If the export from your invoicing system is structurally broken, you get the error report for your software support, free of charge.
Where is my file checked, and is it stored?
On our servers, not in your browser. Your file is used only to check and fix your invoice and to deliver your result. Results are kept so you can download a verified file again for 90 days; validation logs are deleted after 90 days. You can request deletion at any time.

Read on

About UBL: technical details, history and practice →Peppol BIS validator →XRechnung validator →EN 16931 validator →
Related
Countries
E-Invoicing in GermanyE-Invoicing in France
Errors
Netherlands E-Invoice Errors
Answers
What is Peppol BIS Billing 3.0 and how does it work?How do you validate an e-invoice?
Regulations
EN 16931
Validators
XRechnung ValidatorZUGFeRD Validator
Your dataYour file is used only to check and fix your invoice and to deliver your result. Results are kept so you can download a verified file again for 90 days; validation logs are deleted after 90 days. You can request deletion at any time.