How does PDF SignCheck verify a PDF digital signature?

PDF SignCheck cryptographically validates the digital signatures embedded in PDF documents. It checks that the document has not been tampered with after signing, verifies the signer's certificate chain against trusted root Certificate Authorities (CAs), and outputs a stamped PDF with a "Verified ✓" badge — similar to clicking "Trust this certificate" in Adobe Acrobat.

Is my PDF document stored or saved during digital signature verification?

No. Your file is processed entirely in memory on the server. It is never written to disk, never stored in any database, and is discarded immediately after the verified PDF is returned to your browser. We take privacy seriously — your documents remain yours.

What types of PDF digital signatures and certificates are supported?

PDF SignCheck supports PDFs that contain PKCS#7 / CMS digital signatures — the standard used by government portals, official certificate authorities, and digital signing platforms. This includes documents from DigiLocker, e-District, MCA, UIDAI, and similar government services worldwide.

Why does Adobe Acrobat Reader display a PDF signature as "Not Verified"?

Adobe Acrobat only trusts certificates from its own Adobe Approved Trust List (AATL). Many government and institutional signers are not on that list. Our tool auto-trusts the signer's certificate after cryptographic verification — exactly what Adobe asks you to do manually when you click "Trust this certificate." The downloaded verified PDF includes a visual stamp so it's clear the signature has been validated.

Is the online PDF signature verification process cryptographically secure?

Yes. We perform full PKCS#7 signature verification: we extract the signed hash from the signature, independently compute the hash of the document's byte ranges, and compare them. We also validate the certificate chain up to a trusted root CA from the Mozilla CA trust store. This is the same process that Adobe Acrobat and other professional PDF tools use.

Are there daily or rate limits for PDF cryptographic verification?

To prevent abuse, we rate-limit to 10 requests per minute per IP address. The maximum file size is 50 MB. These limits are sufficient for normal usage. If you need higher throughput for enterprise use, please contact us.

Which Indian government certificates and portals are supported?

PDF SignCheck fully supports digital signature verification for official Indian government certificates. This includes UIDAI Aadhaar Cards, state e-District certificates (such as Caste, Income, Domicile, and Birth/Death certificates), DigiLocker-issued PDF documents, NFSA Ration Cards, Income Tax / PAN documents, and any official PDF signed via CCA India (Controller of Certifying Authorities) root credentials.

How do I resolve the "Signature Not Verified" or "Signature Not Checked" warning on Aadhaar or Caste certificates?

Simply upload your signed PDF to PDF SignCheck. Our system extracts the digital signature, cryptographically validates the hash integrity against trusted root certificates, and generates a stamped PDF. When you download this verified document, the signature will show as valid, making it suitable for direct submission.

PDF Redactor

Permanently Redact & Blackout PDFs

Securely censor confidential information, signatures, and private text regions in your PDFs. Runs entirely in-memory — your sensitive data never leaves your device.

SecureSanitizes PDF Bytes

Auto-SearchBatch Pattern Censoring

0B StoredProcessed In-Memory

Daily Limit

Upload your PDF

Drag and drop your file here, or click to browse

.pdf·up to 50 MB

Zero-Knowledge Privacy

Files are processed strictly in secure memory modules inside your local browser. No server storage.

Cryptographic Standards

Fully compliant with IETF RFC 5652 (CMS), Adobe PDF specs, eIDAS, and Controller of Certifying Authorities (CCA).

Verify Anonymously

No personal registration or document tracking is required. Verify up to 2 files daily as guest.

Detailed Audit Trails

Generates downloadable, verified PDFs with structural signature stamps and trust summaries.

Edge Sandbox Security

Verification executes inside sandboxed browser modules to ensure isolated document handling.

Zero Data Logging

Absolutely no logging of files, names, email contents, or signature details. Pure privacy.

Process

How to Redact PDF in 3 Easy Steps

Blackout and delete sensitive PDF contents securely in your browser.

Upload Document

Drag and drop your PDF file into the dropzone above, or click browse to choose a file up to 50 MB.

Define Redact Regions

Search for specific text patterns (emails, SSNs) to auto-blackout, or draw customized blackout regions over page elements.

Apply & Download

Select your redact overlay color (Solid Black/White), click Apply to permanently sanitize the document, and download.

Features

Professional-Grade Redaction Engine

Enjoy permanent sanitization of PDF records with pixel-perfect control.

True Structural Redaction

Removes actual text bytes and layout elements from the PDF structure rather than just drawing cosmetic blocks over it.

Smart Pattern Search

Locate and censor high-risk data points (emails, phones, credit cards) across all pages automatically.

Interactive Region Drawing

Drag and draw custom blackout rectangles directly over signatures, barcodes, or photo segments on any page.

Zero Stored Files

Redactions are applied locally in your web browser. No document uploads are stored on our servers.

Support

Frequently Asked Questions

Answers to common questions about censoring and redacting PDF records.

How does the PDF Redactor work?

Our PDF Redactor lets you mark sensitive text via Search or draw custom blackout boxes over regions (like signatures). It replaces the underlying text and metadata securely in-memory and lays down a solid color block to ensure the data cannot be extracted or recovered.

Is the redaction permanent and safe?

Yes. Unlike simple PDF annotation tools that just overlay colored boxes (which can be easily removed to reveal the hidden text), our tool sanitizes the actual PDF structure. It deletes the hidden text characters from the content stream and overlays solid vector blocks, making the information completely unrecoverable.

Is my PDF document stored on your servers?

No. The visual editing and drawing processes happen entirely in your web browser. When you click Apply, the document manipulation is performed securely in-memory. We do not store, copy, or log your PDF files.

What pattern types can I auto-redact?

You can auto-redact common sensitive patterns like email addresses, phone numbers, SSNs, Aadhaar cards, credit card numbers, or any custom text strings of your choice.

What are the daily usage limits?

Guests get 2 free redaction operations per day. Free registered accounts get 5 operations, and Top-up Credits users get 100 operations. Redaction previews and marking are completely free.

Suite

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Permanently Redact & Blackout PDFs

Zero-Knowledge Privacy

Cryptographic Standards

Verify Anonymously

Detailed Audit Trails

Edge Sandbox Security

Zero Data Logging

How to Redact PDF in 3 Easy Steps

Upload Document

Define Redact Regions

Apply & Download

Professional-Grade Redaction Engine

True Structural Redaction

Smart Pattern Search

Interactive Region Drawing

Zero Stored Files

Frequently Asked Questions

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