Paste a FacturProof VAT-verification certificate below. Its Ed25519 signature is checked in your browser against our published public key — you never have to trust FacturProof, and no call is made to the EU VIES service. A valid signature proves FacturProof asserted this exact verdict, at this time, for this VAT id.
The public key is fetched once from
https://facturproof.com/v1/vat/attestation-key and the check runs entirely client-side
(WebCrypto Ed25519). Nothing you paste leaves this page.