> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/web/digital-signature/samples.md).

# Digital signature samples using JavaScript

Learn how to build a signing application with Sign App, request signatures, sign documents, and review signed documents. Explore the Full API for DigitalSignature to digitally sign and certify PDF doc

### Sign Ap- Repository

Demonstrates building a signing application where users can request signatures on the documents by placing fields, sign documents, review signed documents.

<a href="https://github.com/ApryseSDK/pdftron-sign-app/" class="button primary">Github Repository</a>

## Code Samples

### [Sign and Certify - Digital Signature](/web/get-started/samples/digitalsignaturestest.md)

Demonstrates how to digitally sign a PDF and also how to certify a PDF doc.

### [Validate - Digital Signature](/web/get-started/samples/viewerdigitalsignaturevalidationtest.md)

This sample illustrates how PDFNetJS can be used to validate digital signatures in a document.


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