Tools in This Collection
PDF Sign
Add drawn, typed, or image signatures to PDF pages
PDF Protect
Encrypt PDF with AES-256 password protection
PDF Unlock
Remove password from a PDF you know the credentials for
PDF Hash
Generate SHA-256 checksum to verify document integrity
PDF Repair
Attempt to recover content from corrupted PDF files
PDF Security Workflow
PDF security covers a range of needs: adding a signature to a document, protecting a file with a password, verifying a received document hasn't been tampered with, or recovering a damaged PDF. All five tools here run browser-side — your files are never uploaded to a server.
Adding Signatures to PDFs
The PDF Sign tool lets you add a drawn, typed, or uploaded signature image to any PDF page. Draw with mouse or touchscreen, type your name in a stylized font, or upload a signature image you've previously scanned. The signature is placed on the document as a visual element at the position you choose. This is appropriate for routine approvals, internal acknowledgments, and situations where a handwritten-style signature satisfies the workflow requirement.
Protecting PDFs with Passwords
The PDF Protect tool encrypts a PDF with AES-256 password protection. Recipients need the password to open the document. Set both an owner password (full access, can change permissions) and a user password (open-only). Useful for protecting financial documents, contracts, or any file you want to restrict access to before sharing.
Unlocking Password-Protected PDFs
The PDF Unlock tool removes the password from a PDF you already know the password for. Enter the password, and the tool exports an unlocked version that can be opened without authentication. This is for your own documents — removing encryption from a file you own and have the credentials for.
Verifying PDF Integrity
The PDF Hash tool generates a SHA-256 checksum of any PDF using the browser's built-in Web Crypto API. SHA-256 produces a 64-character fingerprint unique to the file contents — any change to the document produces a completely different hash. Share the hash alongside the document, and the recipient can verify their copy matches by running the same tool. Common use cases: verifying downloaded legal documents, confirming received files weren't corrupted in transit, or documenting a file's state at a specific point in time.
Repairing Corrupted PDFs
The PDF Repair tool attempts to recover readable content from damaged PDF files — truncated downloads, partially corrupted files, or PDFs that fail to open in standard viewers. It parses the PDF structure, extracts recoverable pages and content, and produces a repaired output file. Not all corruption is recoverable, but partial recovery is often possible.
Frequently Asked Questions
Is the drawn signature in PDF Sign legally binding?
The PDF Sign tool creates a visual signature — your drawn, typed, or uploaded signature image placed on the document. This is appropriate for many internal workflows and routine approvals. For legally binding digital signatures with cryptographic verification and audit trails (required for contracts, legal documents, and compliance), use services like Adobe Sign or DocuSign.
What encryption standard does PDF Protect use?
PDF Protect uses AES-256 encryption, the same standard used by financial institutions and government agencies. The password itself is not stored anywhere — if you lose the password, the document cannot be recovered. Keep a secure copy of passwords for encrypted documents.
Can PDF Repair fix any corrupted file?
Repair success depends on the type and extent of corruption. Files that are partially truncated (incomplete downloads) are often recoverable. Files with extensive damage to core structure may only yield partial content. The tool extracts all pages and content it can parse from the damaged structure — some recovery is usually possible even when the file won't open normally.
How does PDF hashing help verify document integrity?
SHA-256 generates a 64-character fingerprint from the exact byte content of the file. The same file always produces the same hash; any change — even one character — produces a completely different hash. By sharing the hash alongside a document, the recipient can confirm their copy is identical to the original by running PDF Hash on their file and comparing the result.