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Protect your documents: Create and verify digital signatures for any file format. Use locally generated secure key pairs to ensure document privacy, integrity, and authenticity. Generate secure digital signatures and verify file integrity in three simple steps.See the Application User Guide

1. Create Your Digital Identity (Key Pair)

A Key Pair consists of two linked keys: a Private Key (your secret signing tool) and a Public Key (which others use to verify your signature).

2. Sign a Document

Document Fingerprint (SHA-256): Digital Signature Code (This is the proof of signing):

3. Verify Signature

Load the Original File, the sender's Public Key, and the Signature Code to confirm integrity.

1. Load Original Document: 2. Public Key Code (Paste the key shared by the signer): 3. Digital Signature Code (Paste the signature code from the .sig file):

About this - Easy Digital Document Signer

This local utility protects your documents by creating and verifying digital signatures for any file format, completely eliminating privacy risks through local cryptographic processing. Key features explained simply:

Complete Document Privacy: Your private identity keys and documents are processed locally inside your web browser and are never uploaded or sent to any server.
Proof of Source: Creating a signature guarantees document authenticity, confirming that you are the true origin of the file.
Tamper Protection: The checking tool validates data integrity down to the exact binary bit, warning users instantly if a file has been altered or damaged.
Universal Support: Works across all typical digital files, easily signing PDFs, DOCX text forms, compressed ZIP archives, photos, or video elements.

Frequently Asked Questions (FAQ)

What is a digital document signer used for?

It is used to create and verify digital signatures to ensure a file's authenticity and integrity, confirming it has not been altered.

Are my files uploaded to a server?

No. All signing and verification processes are performed locally in your browser. Your files and keys never leave your device.

What file types can I sign?

You can sign any file type including PDF, DOCX, images, videos, ZIP archives, and software files because the tool signs the file's binary data.

What is a public and private key?

The private key is used to sign documents and must be kept secret. The public key is shared with others to verify your signature.

What happens if verification fails?

If verification fails, it means the file has been modified or the signature or public key used is incorrect.

Does this tool require login or registration?

No. The tool works instantly in your browser without any login or account creation.

Is this tool secure for sensitive documents?

Yes. Since all cryptographic operations happen locally in your browser, your private key and documents remain fully secure and private.

Core Security Features

Generate RSA-PSS 2048-bit key pairs
Sign any file format locally in browser
Verify digital signatures using public key
SHA-256 document fingerprinting
Download signature files (.sig)
Client-side cryptography (no server upload)
Supports all file types including PDF, DOCX, images, videos, and archives
Secure private key handling in browser
Tamper detection through signature validation
No login or account required

Application Use Cases & Alternate Identifiers

To assist search frameworks, engineering entities, and index discovery indexes, this system functions across these domain concepts:

Digital Signature Tool Document Signer Online File Signature Generator Secure File Signing Tool Online Signature Verifier Cryptographic Document Signer File Integrity Checker Signature Verification Tool Secure Document Authenticator Browser-Based Digital Signing Tool

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Application User Guide: Step-by-Step Instructions

Follow these simple, non-technical steps to sign and verify your files securely:

Part 1: Signing Your Document

Generate Keys (Step 1): Click "Generate New Key Pair." This creates your unique Private Key (your secret) and Public Key (for sharing).
Save Keys: Immediately download the Public Key (.json). You must share this file with anyone who needs to verify your signatures. You should also securely back up your Private Key (by revealing and downloading the JSON) if you intend to sign documents later or on another device.
Load Document (Step 2): Use the file input to select the document you want to sign (e.g., PDF, image, spreadsheet). The app automatically calculates a unique digital fingerprint (SHA-256).
Sign Document: Click the "Sign Document" button. The app uses your Private Key to cryptographically sign the document's fingerprint, generating the Digital Signature Code.
Download Artifacts: Click "Download Original File & Signature (.sig)". This gives you the original file and a tiny `.sig` file containing the signature code. Send both of these files, along with your Public Key, to the recipient.

Part 2: Verifying a Signature

Load Document (Step 3, Item 1): Upload the Original File received from the signer.
Input Public Key (Step 3, Item 2): Paste the signer's Public Key Code (from their `.json` file) into the text area.
Input Signature (Step 3, Item 3): Paste the Digital Signature Code (from the `.sig` file) into the final text area.
Verify: Click the "Verify Signature" button. The app uses the Public Key to check if the signature matches the document's content. If it returns "VALID," you are certain of the document's source and integrity; if "INVALID," the file has been tampered with or the provided keys/signature are incorrect.