What this invoice is for
An EU VAT invoice follows the fields in the VAT Directive: both names and addresses, your VAT number, a sequential number, the taxable amount and rate, and the VAT due. Intra-EU services say Reverse charge and need the customer’s VAT number. Intra-EU goods are exempt under Article 138. Exports outside the EU are exempt under Article 146. Rates are the national rates for the member state you select, not one EU-wide rate, and they do not include regional exceptions such as the Canary Islands or the Azores.
Some countries also require the invoice to be filed through a national e-invoicing system. This tool does not do that filing. UK VAT is a separate set of rules.