OpenP7M

In Italy, signed documents and electronic invoices often arrive as .p7m files, a signature container rather than a document format. As the site points out, renaming the extension doesn't work. OpenP7M opens the container in the browser and shows what's inside. For a .pdf.p7m that's the signed PDF. For an .xml.p7m it's a FatturaPA invoice, which the reader can display as a readable layout alongside the original XML.

There are fictional sample files to try before using a real document, and the reader tells you up front if something inside isn't supported.

Reading is free, with every page visible under a preview watermark. If you need a clean copy, export costs €1.99 per source file as a one-time payment. One file at a time needs no account. Batch mode handles up to 50 files or 100 MB per batch, with a 50 MB limit per file, and requires an account.

This matters more than usual because these files are invoices and contracts. The privacy policy, updated October 26, 2026, says the document is read into browser memory and that unpacking, display and export all happen there, so P7M content, filenames, invoice fields and certificate data aren't sent to the server. What the service does receive is a cryptographic fingerprint of the file to link it to a purchase, plus order, Stripe and technical log data. Accounts use a self-hosted Supabase Auth service. The policy names the operator as Hinstein, an independent developer based in Hong Kong, and notes that Hinstein is a public name rather than a registered company.