Choose a P7M file
Open an attached CMS SignedData file up to 12 MB locally in your browser.
Inspect a signed CMS container on your device.
P7M Viewer
Inspect an attached CMS SignedData envelope and its embedded payload locally in your browser.
Certificate identities are descriptive; signature integrity and trust are not verified.
Signed File ViewerYOUR WORKSPACE
Your task
Inspect P7M
Choose a file to inspect it here.
Also with this file: Download payload
Processed privately in your browserNo uploadNo signup
A simple workflow
Three steps. One less thing to do.
Inspect the envelope
Review signers, embedded certificate metadata, payload type and clear verification limits.
Extract the payload
Download the original embedded bytes with a safe name; the payload is never opened automatically.
Made for the everyday
A useful part of your workflow.
Recover an attachment
Extract an attached PDF, XML, text file or opaque payload from a P7M envelope.
Certificate inspection
Read embedded subject, issuer, serial and validity dates without interpreting them as trust.
Invoice handoff
For a supported embedded invoice XML, reuse the existing invoice reader to show source fields.
Good to know
A few useful answers.
The details that matter before you use Signed File Viewer.
Does this prove the signature is valid?
No. This version parses the CMS envelope and extracts the attached bytes. It does not verify signature integrity, certificate chain, revocation or legal validity.
What kinds of P7M work?
Attached CMS SignedData with data content and at least one signer. Detached signatures, encrypted CMS and malformed containers are rejected.
Will a PDF or XML open automatically?
No. Files remain inert until you choose a local download. XML text shown in the workspace is escaped, not executed.
What certificate details are shown?
Embedded certificate subject, issuer, serial and validity dates when present. Embedded does not mean trusted or current.
Does my file leave my device?
No. Parsing and extraction run in your browser. File content, filenames and certificate identities are excluded from analytics.
What are the limits?
One CMS file up to 12 MB with an attached payload up to 10 MB. Larger or detached containers need a later review.
Can it read e-invoice XML?
Supported embedded invoice XML is passed to the existing E-Invoice parser; this workspace does not duplicate invoice syntax or claim compliance validation.