Blog
Tips, guides, and updates about PDF editing and document privacy.
What Is OCR and How Does It Work in a PDF?
OCR turns scanned pages and images into selectable, searchable text. Learn what OCR is, when you need it, and how RedaktPDF runs it privately in your browser.
How to Redact a PDF for GDPR Compliance
A practical guide to redacting personal data from PDFs under GDPR — which fields to remove, how Article 17 erasure works in practice, and how to make the removal defensible in an audit.
PDF Redaction vs. Black-Box Overlay: Why the Difference Matters
A black rectangle painted over text in a PDF is not the same as redaction. This post explains how PDFs actually store content, why overlays can be reversed, and what real redaction does.
How RedaktPDF Encrypts Your PDFs: A Deep Dive Into Our E2EE Architecture
A technical walkthrough of RedaktPDF end-to-end encryption — PBKDF2 key derivation, AES-256-GCM encryption, key wrapping hierarchy, and zero-knowledge architecture. Real Web Crypto API code included.
How to Add an Image to a PDF (Including a Signature)
Insert an image or signature into any PDF page in seconds — no software to install, works on any device.
How to Add Text to a PDF Without Adobe Acrobat
Add text boxes, choose from 33 fonts, and position text anywhere on a PDF page — free, in your browser, no account required.
How to Rearrange, Delete, and Rotate PDF Pages Online
Rearrange, delete, and rotate pages in any PDF — drag to reorder, delete unwanted pages, fix sideways scans — all free in your browser.
How to Redact Sensitive Information from a PDF
Learn how to permanently remove sensitive data from PDF documents. Avoid common redaction mistakes and protect confidential information.
Why End-to-End Encryption Matters for PDF Editing
Most online PDF tools process your files on their servers. Learn why end-to-end encryption is essential for protecting sensitive documents.
A Guide to PDF Annotations: Highlights, Notes, and Markups
Learn how to annotate PDFs effectively. From highlighting key passages to adding freehand drawings, this guide covers all the annotation types you need.
How to Edit a PDF Without Adobe Acrobat
You don't need an expensive Adobe subscription to edit PDFs. Learn about free browser-based alternatives that work without installing software.