I Built a Free Tool to Verify Aadhaar eSign PDFs — Here's Why It Matters
A few weeks ago I got a signed contract PDF from someone.
It had a little stamp in the corner:
"Digitally Signed by Rahul Sharma, Date: 2026-06-01."
I had absolutely no idea if that signature was actually valid.
Not because verification is impossible, but because there wasn't a simple tool that gave me a clear answer.
Adobe Reader gave me a partial result. Some online tools asked me to upload documents to unfamiliar services. Government portals could be difficult to understand. And many people don't know the difference between a scanned signature and a genuine digital signature.
So I built SigVerify — a simple tool that helps verify digitally signed PDFs, including Aadhaar eSign and DSC-signed documents.
The Problem Nobody Talks About
Digital signatures are now widely used in India.
Aadhaar eSign, DSCs and other electronic-signature services are used for contracts, government documents, financial paperwork, applications and many other workflows.
But there is an important distinction:
A scanned signature image is not the same thing as a cryptographic digital signature.
Drawing your name on a touchscreen isn't necessarily a digital signature.
A picture of a handwritten signature pasted into a PDF doesn't prove who signed the document or whether the document was modified afterwards.
A genuine digital signature contains cryptographic information that can be independently examined.
A proper verification process can help answer questions such as:
- Who signed the document?
- Is the associated certificate valid and trustworthy?
- Was the document changed after signing?
- When was the document signed?
- Does the signature pass cryptographic verification?
The problem is that most people don't have an easy way to understand these answers.
That's where SigVerify comes in.
What SigVerify Does
You upload a digitally signed PDF and SigVerify analyzes the available signature information and presents the result in a human-readable format.
Depending on the document, the result can include:
- ✅ Signer information
- ✅ Certifying Authority
- ✅ Signing timestamp
- ✅ Document integrity/tamper status
- ✅ Certificate information
- ✅ Certificate chain information
- ✅ Certificate fingerprints
- ✅ Revocation information where available
- ✅ Signature validity
- ✅ Signing-time validity information
Instead of forcing users to understand complex certificate and signature data, SigVerify turns the important information into a clear verification report.
The Aadhaar eSign Challenge
Aadhaar eSign has an interesting verification problem.
Some Aadhaar eSign workflows use certificates with a short validity period around the signing session.
That means a document signed months ago can contain a certificate that is no longer currently valid.
Simply checking whether the certificate is valid today can therefore produce a misleading result.
For this reason, verification needs to consider the certificate's validity and the signing information in the context of when the document was actually signed.
SigVerify takes this into account when evaluating supported Aadhaar eSign documents.
The goal is simple:
Don't judge an old document only by what its certificate looks like today. Consider the evidence surrounding the original signing event.
Built for Real-World Documents
SigVerify is designed for people who receive digitally signed documents in everyday work.
⚖️ Legal professionals
Verify digitally signed contracts, agreements and documents before relying on them.
📊 CA firms and auditors
Check digitally signed financial and compliance documents.
🏢 Businesses and HR teams
Verify digitally signed agreements and employee documents.
👨💻 Developers
Understand and test digital-signature verification results.
👤 Individuals
Check whether a digitally signed document they received or signed passes verification.
Supported Signatures
SigVerify is designed to work with a range of commonly encountered digital-signature ecosystems, including Indian signing authorities and widely used electronic-signature platforms.
Support may vary depending on the document and signature format.
The goal is to continuously expand compatibility as more real-world document formats are encountered.
Simple, Pay-As-You-Go
SigVerify is designed to remain simple.
New users receive a free verification credit after signing in.
After the free verification, additional verification credits are available on a pay-as-you-go basis.
There is no complicated subscription required just to verify an occasional document.
Privacy Matters
Digital documents can contain sensitive information.
SigVerify is designed with document privacy in mind and only processes documents for the verification functionality provided by the service.
For complete details about how data is handled, please refer to the SigVerify privacy policy.
What's Next
SigVerify is still evolving.
Some areas we're working on include:
- More signature and certificate compatibility
- Better verification explanations
- Batch verification
- Developer/API access
- Additional international certificate support
- Improved verification reports
The focus is not on adding features just for the sake of adding them.
The goal is to make digital-signature verification simple, reliable and understandable.
Meet Panda 🐼
Behind SigVerify's verification experience is our in-house verification engine, Panda.
Panda handles the complex verification work behind the scenes and turns the results into information that ordinary users can understand.
You don't need to know how certificates, signatures or cryptographic validation work.
You provide the document. Panda handles the verification. 🐼
Try SigVerify
If you work with digitally signed PDFs — contracts, government documents, Aadhaar eSign documents, business paperwork or other electronically signed files — give it a try.
If you find a problem or have an idea that could make verification easier, I'd love to hear from you.
— Gaurav Kalal (@gorupa)
*Built to make digital-signature verification a little less confusing.