Financial standards reference
Open reference material behind the validators: EN 16931 rules, ISO 20022 schemas, e-invoicing mandates, bank identifiers and terminology.
ValidateFin resources
ValidateFin publishes free reference documentation on the standards its validators enforce: the 319 EN 16931 business rules that govern European e-invoices, the ISO 20022 schema families (pain.001, pain.008, camt.052/053/054) with their namespaces and versions, e-invoicing mandates country by country, a directory of 6,203 banks with their BIC codes, and a 93-term glossary. All pages are free, require no signup, and every validator runs entirely in the browser.
Compliance deadlines
2 regulatory deadlines that change what your files must contain: a countdown, who is affected, a checklist, and the validator that proves you are ready.
TARGET closing days
The six days a year TARGET is closed, listed for 21 years: the days that are not SEPA Inter-PSP Business Days. National bank holidays are not among them.
E-invoicing
E-invoicing mandates in 32 European countries: obligations, formats and rollout dates.
EN 16931 rules
The 319 EN 16931 business rules explained, each with the cause of the error and how to fix it.
EN 16931 business terms
The 163 EN 16931 business terms (BT-*): cardinality, data type and the UBL ↔ CII ↔ Factur-X mapping.
ISO 20022 schemas
The 22 ISO 20022 schema families (pain, camt): namespace, root element and versions.
Code lists
7,201 coded values (VATEX VAT exemptions and more) with their official meaning, source and JSON download.
SEPA rejection codes
The 106 pain.002 reason codes (AC04, AM04, MD01…): what each means, whether you can resubmit, and how to fix it.
NAV result codes
The 269 codes the Hungarian tax authority returns on an invoice report, 118 of them blocking — each with its official message and the condition that triggers it.
Sample files
131 ready-made SEPA, camt.053, UBL, MT940 and Factur-X files — valid and deliberately broken, each checked by its own validator.
Bank directory
6,203 banks across 38 countries, with their BIC codes and national bank identifiers.
Glossary
93 finance and e-invoicing terms defined in plain language.
MCP server
Run the validators from Claude, Cursor or any MCP client. 100% local, no upload.