Free Online P7M (Digitally Signed File) Viewer (No Signup)
Also opens DWG, DXF, STEP, IGES, IFC, SKP, STL, OBJ, GLB, FBX, 3DM and other 3D/CAD files. Drop any file on the viewer.
Works directly in Chrome, Firefox, Safari, and Edge
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What Is a P7M (Digitally Signed File) File?
A .p7m file is a CMS (PKCS #7) SignedData envelope in the CAdES form that qualified electronic signatures use across Europe, and above all in Italy. It holds the signed file unchanged, the signature and the certificate of the person who signed. The name keeps the original extension: plan.dwg.p7m is plan.dwg, signed. A file signed twice ends in .p7m.p7m.
This viewer takes the envelope off in your browser and opens the signed file with its own readers: a PDF as a document, a DWG, DWF or DXF as a drawing, an IFC as a building model, an XML invoice as text. The status line names the signer and the signing time when the certificate carries them.
The signature is not verified. The viewer shows what was signed and who signed it, and does not check that the signature or the certificate is valid; use a recognised signature app for that. For zipped files, see the ZIP viewer.
Who Uses P7M (Digitally Signed File) Files?
Architects, engineers, surveyors and contractors who receive signed drawings and models from public administrations, professional bodies and clients: Italian building permits (pratiche edilizie), tenders and documents sent by certified email (PEC) arrive as .p7m. Also anyone handed a .p7m on a computer or phone with no Dike, ArubaSign, GoSign or other signature app installed.
Common Use Cases
- Open a signed DWG or DWF drawing (.dwg.p7m, .dwf.p7m) without a signature app
- Read a signed PDF (.pdf.p7m) in the browser
- Look at a signed IFC model sent to a public administration
- Read a signed FatturaPA XML invoice (.xml.p7m) on the text sheet
- See who signed a file and when
- Export the signed drawing or model to another format once it is open
Features
Opens .p7m, .p7m.p7m and .tsd
CAdES and PKCS #7 envelopes in DER or BER, signed once or several times, and RFC 5544 time-stamped envelopes.
The Signed File Opens
PDF, DWG, DWF, DXF, IFC, XML and everything else the viewer reads by itself, under the file’s own name.
Signer and Signing Time
The signer’s name and the signing time, when the certificate in the envelope carries them.
Signature Not Verified
The status line says plainly that the signature has not been checked.
Base64 and PEM Text
.p7m files saved as base64 text, with or without a PEM header, open too.
Detached Signatures Explained
A .p7s with no signed file inside gets a clear notice asking for the original.
No Signature App Needed
Works on Windows, macOS, Linux, ChromeOS, iOS and Android, with nothing to install.
Export the Signed File
Once open, a drawing exports to PDF, DXF or a picture and a model to GLB, OBJ, STL or STEP.
Nothing Is Uploaded
The envelope is opened and the file read entirely in your browser. No account, no copy on a server.
Share and Embed
Send a link that opens the file in any browser, or put the viewer in your own page with one iframe.
Compatibility & Format Notes
Envelopes: CAdES and PKCS #7 SignedData in DER and in BER (indefinite lengths, content split into chunks), files signed more than once (.p7m.p7m), .p7m files saved as base64 text with or without a PEM header, and RFC 5544 time-stamped .tsd envelopes.
What opens: the signed file, under its own name, through the same readers as any upload: PDFs, CAD drawings, 3D and BIM models, archives, Office documents, pictures and text.
Not included: a detached signature (.p7s) holds the signature and certificate with no signed file, and a lone time-stamp token holds no file either; the viewer says so and asks for the original. Signatures and certificates are never verified.
Embed on Your Website
Add this viewer to your own site with a single line of HTML. Click Embed in the toolbar to generate an embed code, or use the snippet below with your own file URL.
Your Files Stay on Your Computer
Your P7M (Digitally Signed File) files are parsed entirely in your browser. Nothing is uploaded, stored, or shared unless you explicitly click the Share button. Shared files are hosted for 90 days then deleted.
Frequently Asked Questions
▶How do I open a .p7m file?
Drag it onto this page. The viewer takes the signature envelope off in your browser and opens the file inside it, on Windows, macOS, Linux, Android or iOS, with nothing to install.
▶Is the signature verified?
No. The viewer shows the signed content, and the signer’s name and signing time when the certificate carries them, but it does not check that the signature or the certificate is valid. Use a recognised signature app for a legal check.
▶What is a .p7s file?
A detached signature: it holds the signature and the certificate but not the signed file. Upload the original file, which usually travels with it under the same name without .p7s.
▶Can I get a PDF out of a .pdf.p7m?
Yes. The signed PDF opens in the PDF reader, where it can be read, printed and downloaded as a plain PDF.
▶Is this P7M viewer really free?
Yes, completely free. No signup, no watermarks, no file size limits on the viewer (the optional share-link feature has a 100 MB upload cap). Built by Innerscene as a tool for architects, engineers, and designers.
▶Are my files uploaded to a server?
No. All parsing, rendering, and conversion runs in your browser: nothing is uploaded, stored, or transmitted by default. The Share button is the only feature that uploads a file, and only when you explicitly click it.
▶Can I convert to another format?
The signed file exports like itself once it is open: a drawing as PDF, DXF or a picture, a model as GLB, OBJ, STL or STEP, a PDF as a PDF.
▶Can I embed this viewer on my own site?
Yes. Click Embed in the toolbar to generate a one-line <iframe> snippet you can paste into any HTML page. You can choose whether the embed shows the viewer’s toolbar.