How to open a P7M file online

A .p7m file is a container that can include a document and signature information. The extension does not tell you whether its contents are PDF, XML or another format.

Open the free reader

Select and read

1. Save the attachment to your device and keep the original P7M.
2. Choose one file in the reader. No account is needed.
3. Preflight checks structure and limits. Extraction locates the original contents.
4. Read a supported PDF, text or invoice and use the download button for the actual content format.

Contents stay in your browser. The website still downloads its own resources over the network.

When a file cannot be read

This release supports binary DER/BER CMS SignedData containers. Encrypted files need other tools and credentials; Pro does not unlock them. Detached signatures require the original document. PEM, Base64 and full S/MIME messages are outside the stated compatibility.

A resource limit or unsupported preview does not prove corruption. Successful extraction can still provide the original download.

Reading and checking signatures

Reading is separate from local cryptographic checks. Results distinguish not checked, unsupported and indeterminate. Trust chains, revocation and trusted time are not checked. No result establishes legal signature validity.

See the XML/P7M invoice guide or PDF extraction guide.