Open Xsig Files Online and Save to PDF
Free. The file never leaves your device. Works on phone and computer.
Download the documents enclosed inside Spanish electronic signatures and inspect signer data. Our online xsig viewer is what you need when an administration or business portal sends an .xsig attachment that will not open: the tool extracts the readable document directly in your browser.
Use our xsig viewer to read files
Select your .xsig file to preview its contents. SignedDocs decodes both enveloping signatures where the PDF is stored inside XML tags and enveloped signatures where the XML itself forms the document:
- Extract embedded PDF copies from enveloping XMLDSig and XAdES structures
- View signer identities, issuing authorities, and signing dates in the signer card
- Download the extracted document as a clean PDF or retrieve the original XML package
- Inspect accompanying .csig binary files with automatic format routing
Signature verification details
SignedDocs extracts and formats the cryptographic metadata recorded inside the signature. It does not certify legal validity against Spanish government trusted lists. For an official administrative check, utilize the Spanish government VALIDe portal or the EU DSS validator. SignedDocs is not a government agency.
Open files in our xsig viewer anytime
Upload your document in the reader panel above to extract and save your PDF. The tool runs locally across desktop computers, tablets, and mobile phones with complete privacy, zero file uploads, and no user registration.
What is an .xsig file?
An .xsig file is an XML-based electronic signature format common in Spain, adhering to XMLDSig or XAdES standards to encapsulate signed documents and certificates.
Where did I get it?
You typically receive .xsig files from Spanish public administration portals, regional registries, tax portals, and e-government platforms.
Is it safe?
Yes. SignedDocs processes .xsig files locally within your web browser. No documents or personal details ever leave your machine.
Why won't it open by double-click?
Computers do not associate .xsig files with standard document readers. Because the content is encapsulated inside XML markup, a viewer is needed to unpack the document.
How to open it on iPhone/Android?
Navigate to this webpage on mobile Safari or Chrome, upload the .xsig file from your phone storage, and view the extracted document instantly.
Is the PDF still legally valid?
The PDF you download is a copy of the content. The proof of the signature is the original file. Save that file. This page is not a legal validation.
What is the difference between .xsig and .csig?
An .xsig file uses XML-based signature structures (XMLDSig/XAdES), while a .csig file contains binary CMS/CAdES signatures. SignedDocs inspects the bytes to handle each format correctly.
Other formats: .p7m · .p7s · .tsd · .zfo · .es3 · .xades · .asice · .adoc