P7M Viewer: open a .p7m file online
Choose a .p7m file: the document inside is taken out of the signed envelope in your browser and shown, with the signer details. Nothing is uploaded.
Free · runs in your browser · nothing is uploaded
At a glance
A .p7m file is a CAdES (CMS / PKCS#7) signed envelope that holds a document, its signature and the signer's certificate; this viewer opens it in the browser, shows the document and the signer details, and lets you download the original file.
- Opens binary and Base64 .p7m files up to 30 MB, including nested .p7m.p7m envelopes and several signers.
- Shows a PDF page by page, images, text and Italian FatturaPA invoices as a readable invoice; the original file can be downloaded unchanged.
- The signature is checked against the content and the certificate inside the file; chain of trust, revocation and legal value are not checked.
- Nothing is uploaded: the page shows 0 requests to other servers.
Sources: RFC 5652 – Cryptographic Message Syntax (CMS) (checked 2026-10-27) · ETSI EN 319 122-1 – CAdES digital signatures (checked 2026-10-27)
How to use the P7M file viewer
- Click “Choose a .p7m file”, or drag your file onto the page. Files up to 30 MB are accepted.
- The envelope opens in the tab. Nested layers (a file signed more than once) are opened one after another, up to 5 levels.
- Read the signer box. It lists each signer’s name, organization, an identifier from the certificate (Italian certificates usually carry the person’s tax code, shown as TINIT-…), the issuer, the valid-from and valid-to dates, the signing time, the serial number, and the hash algorithm such as SHA-256.
- Look for extra flags. They appear only when they apply: self-signed certificate, expired certificate, certificate not valid at the signing time, or a timestamp token.
- Read the content. A PDF is drawn page by page (the first 30 pages), an invoice appears in the Document tab with the raw XML in the XML tab, and images and text files are shown directly.
- Click “Download the extracted PDF”, “Download the extracted XML”, or “Download the extracted file” to save the content.
If you want to test the viewer first, click “Try a signed invoice” or “Try a signed PDF”. Those files are signed with a throwaway TEST certificate. For an invoice, “Print / save as PDF” gives you a printable copy. The viewer opens one file at a time.
Does opening a .p7m file check the digital signature?
Only in part. The viewer checks that the signature fits the content and the certificate stored inside the file, so a single changed byte produces “signature does not match”. It does not check who the signer really is: the name, tax code and issuer are read from the certificate, and anyone can make a certificate with the same name. It also does not check whether the certificate is trusted, revoked or qualified, and it does not confirm legal validity.
| What the page shows or checks | What it means |
|---|---|
| Signature matches the content | Checked with the browser’s WebCrypto against the content and the certificate inside the file |
| Name, organization, identifier, issuer | Read from the certificate; not checked against any register |
| Valid-from and valid-to dates | Read from the certificate |
| Signing time | Stated by the signer inside the file; it proves nothing unless it comes from a trusted timestamp |
| Hash algorithm (e.g. SHA-256) | Shown so you can see which algorithm was used |
| Chain of trust (EU Trusted Lists, Italian lists) | Not checked |
| Revocation (OCSP/CRL) | Not checked |
| Signature policy and qualified status | Not checked |
| Timestamp token | Flagged when present, not checked |
| Legal value | Not checked; use an official or qualified validation service |
How do I get the PDF out of a .p7m file?
Open the file in the viewer and save the document inside the envelope. The saved PDF is exactly the document that was signed, without the signature envelope around it.
- Choose your .p7m file and wait for the signer box to appear.
- Check that the signature matches the content and read the signer details, remembering that the name and issuer are not verified.
- Click “Download the extracted PDF” to save the document.
- Keep the original .p7m file as well. It is the only copy that still carries the signature; the saved PDF is byte for byte the document that was signed.
Why do I get .p7m files from Italy?
In Italy the .p7m extension is everywhere: signed e-invoices sent through the SdI exchange system often arrive as .xml.p7m (some are signed another way and stay .xml, and many business invoices are not signed at all), and signed contracts and official documents often come as .pdf.p7m. A computer without a signature program shows such a file as unknown, which is why a browser-based viewer helps. The Italian version of this page is Aprire file p7m.
How this tool works and where the numbers come from
The file is read in your browser: the CAdES envelope (CMS, RFC 5652) is opened with the PKI.js library and the signature is checked against the content and the certificate stored in the file with the browser’s WebCrypto. The chain of trust, revocation and legal value are not checked. PDFs are drawn with pdf.js; Italian FatturaPA invoices are read field by field.
Sources
Frequently asked questions
What is a .p7m file?
A .p7m file is a signed envelope in the CMS format, whose older name is PKCS#7 (RFC 5652). It holds the original document, the signature and the signer’s certificate. The envelope is signed, not encrypted, so the content can be read once it is opened. A signed S/MIME message can also arrive as a .p7m; the viewer opens the envelope but shows the mail inside as raw message text, not as a formatted email; an encrypted S/MIME message needs the recipient’s private key, and this viewer cannot open it.
What is a .pdf.p7m or .xml.p7m file?
The first part of the name shows what is inside the envelope. A .pdf.p7m wraps a PDF, and a .xml.p7m usually wraps an Italian FatturaPA e-invoice received through the SdI system. Any file can be inside: the viewer shows a PDF page by page, an image, a text file, or an e-invoice as a readable invoice, and offers other types, such as Word or Excel files, for download.
Is the file uploaded?
No. The tool runs entirely in your browser tab and nothing you open is uploaded; the page shows that it made 0 requests to other servers. It accepts .p7m files up to 30 MB.
Does it work on Mac, Windows and phones?
Yes. It runs in any modern browser tab, so there is nothing to install on a Mac, a Windows PC or a phone.
Does saving the PDF keep the digital signature?
The saved PDF is the document that was inside the envelope, and the .p7m signature envelope is not part of it. Keep the original .p7m file if you may need to show the signature later.
How do I create a P7M file?
This tool only reads files. It cannot create or add signatures; creating one needs a digital signing certificate and signing software.
Can I open several files at once?
No. The viewer opens one file at a time.
What happens with .p7m.p7m files, several signers or a .p7s file?
A file signed twice, such as .xml.p7m.p7m or .pdf.p7m.p7m, is opened layer by layer, up to 5 layers, and every layer’s signer is listed; an envelope with several signers lists all of them. A .p7s file is a detached signature that holds only the signature, so the viewer cannot open it on its own: you need the original file as well.
Related tools
- Aprire file p7m: the Italian version of this viewer, useful if you prefer the interface in Italian.
- P7M to PDF: use it when you specifically want the invoice inside converted to a PDF.
- Visualizzatore fattura elettronica: use it to read an Italian FatturaPA e-invoice (.xml or .xml.p7m) with the codes explained, in Italian.
- Fattura elettronica forfettari: for Italian flat-rate freelancers who need to create an e-invoice.
- XRechnung Viewer: the German page for reading an XRechnung e-invoice (XML), if the file you received is not Italian.
- E-invoice validator and viewer: use it to check and read an e-invoice in more detail.