Document & Format Validator

B2Brouter provides two ways to validate an electronic document: an online tool for manual checks, and an API endpoint for programmatic validation. Both apply the same validation rules.

Online validator

The online validator is a free web tool for checking documents manually, without writing any code.

Access it at app.b2brouter.net/en/validation.

How to use it

1. Go to app.b2brouter.net/en/validation.
2. Upload your XML file.
3. Click Validate.

The tool returns a list of errors and warnings, each with the XPath location of the problematic element and a description of the rule that failed.

API endpoint

The /documents/validate endpoint lets you validate documents programmatically. Use it to integrate validation into your application, CI pipeline, or automated workflow.

See the full API reference at developer.b2brouter.net/reference/validate-document.

Authentication is required. The endpoint accepts a document file and returns structured validation results.

What gets validated

Both the online tool and the API endpoint check:

• Schema compliance — whether the XML structure matches the format specification (e.g. UBL 2.1, CII D16B).
• Business rules — whether mandatory fields are present and values are within allowed ranges.
• Schematron rules — format-specific validation rules defined by the standard (e.g. Peppol BIS rules, EN 16931).
• Model DB — field-level checks against our database in relation to what the tax authority requires.
• Tax report — for invoices that generate a tax report, validation of the invoice values needed to produce a valid tax report.

Neither tool checks whether the receiver exists or whether the routing information is correct — that happens at sending time.

Validation when creating a document via API

The same validation runs automatically when you submit a document through the API (e.g. POST /documents). If the document does not pass, the API returns a validation error and the document is rejected before it enters the system.

This means you do not need to call /documents/validate separately before every submission — but it is useful for debugging and pre-flight checks during development.

Reading the results

Result	Meaning
Valid	The document passes all schema and business rules for the selected format.
Warning	The document is technically valid but contains values that may cause issues with some receivers.
Error	The document does not conform to the format. It will be rejected if submitted.

Fix all errors before using the document in a real integration. Warnings are informational but should be reviewed.

Supported formats

Both the online tool and the API support the main formats accepted by B2Brouter, including:

• Peppol BIS Billing 3.0 (UBL)
• EN 16931 (European standard)
• Factura-e (Spain)
• FatturaPA (Italy)
• UBL 2.1 Invoice / Credit Note

The full list of available formats is shown in the format selector on the validation page.

Common use cases

• Before going live — validate sample documents from your ERP or billing system to catch integration issues early.
• Debugging API errors — if the API returns a format validation error, use the online tool to get a detailed breakdown.
• Testing new formats — when adding support for a new country or format, validate your output before running end-to-end tests.
• Automated pre-flight checks — call /documents/validate from your CI pipeline or integration layer before submitting documents to production.