Check whether a digitally signed PDF is genuine: see who signed it, when, and whether anything was changed after signing. Works with DSC-signed Form 16, GST and eSign documents.
Click or drag a signed PDF here
A digital signature in a PDF holds two things: a fingerprint (hash) of the document at the moment it was signed, and the signer's certificate. This tool recalculates the fingerprint from your file and checks it against the signed value, then checks the signature itself with the public key in the certificate. If both match, the document is exactly what the signer signed.
Everything runs in your browser, so confidential documents such as salary certificates, contracts and invoices never leave your device.
Checking Form 16 and Form 16A from TRACES, GST registration certificates and returns, DSC-signed company documents, Aadhaar eSign agreements, offer letters, digitally signed invoices and court or government orders before you rely on them.
Yes. A digital signature stores a fingerprint (hash) of the document. The tool recalculates it from your file and compares it with the signed value. If even one character was edited after signing, the check fails.
Open this page, choose the Form 16 PDF downloaded from TRACES or given by your employer, and the tool shows who signed it, when it was signed and whether the file is unchanged. A green result means the content matches what the employer signed.
Adobe marks a signature as unknown when the certificate's issuing authority is not in its list of trusted roots on your computer. This is common with Indian DSC certificates. It does not mean the document was changed; this tool shows whether the content is intact.
No. The tool confirms the file is unchanged and the signature matches the certificate inside it, and shows who issued that certificate. Checking the certificate against trusted authorities and revocation lists needs online services; Adobe Acrobat Reader can do that.
No. A scanned signature is only an image and carries no cryptographic data, so nothing can be verified. Only digital signatures (DSC, eSign, Aadhaar eSign and similar) can be checked.
No. The file is read and checked inside your browser. It is never sent to TooliFyra or any other server.
