SwiftPDFLab Knowledge Base
Step-by-step guides for SwiftPDFLab’s Editor and standalone PDF tools. All guides are free, and your documents are processed locally in your browser.
Editing PDF Text
How to Edit Existing Text in a PDF
Replace words, change font size, and apply Bold or Italic where the document allows it.
Real Text Editing vs Overlay
What genuinely changing text means, and how it differs from covering it with a shape.
Why Can’t I Edit Some PDF Text?
Fonts, layout space, protections, and why a refused edit is protecting your file.
Edit PDFs Privately in Your Browser
How local document processing works, and how it differs from website analytics.
Why PDF Editing Isn’t Like Word
Fixed layout, embedded fonts, and no automatic reflow — explained in plain language.
Edit PDF Text on Mobile
The touch workflow on a phone or tablet, plus honest limits on small screens.
Browse All Guides
Getting Started
Learn how to open, edit, and save your first PDF.
How to Annotate PDFs
Highlight, underline, strikethrough, text notes, shapes, callouts, and watermarks.
How to Sign PDFs
Draw, type, or upload your signature and place it on any page.
How to Fill PDF Forms
Complete interactive PDF form fields directly in your browser.
Merge & Split PDFs
Combine multiple PDFs or split a PDF into separate files.
Compress PDFs
Reduce PDF file size while maintaining quality.
Redact PDFs
Permanently black out sensitive content.
Security & Encryption
Encrypt, decrypt, change permissions, and remove restrictions from PDFs.
Complete Tools Guide
Comprehensive guide to the dozens of tools in SwiftPDFLab Editor.
Measure Distance & Area
Measure distance, area and perimeter on any PDF page in the Editor.
Add Page Labels
Add Roman numerals, letters or custom labels to PDF pages.
OCR & Searchable PDFs
Make scanned PDFs searchable with private, client-side OCR.
Bookmarks & Table of Contents
Add a navigable outline or a clickable contents page.
Compare Two PDFs
Spot added, removed and changed content between versions.
PDF Attachments
Embed, manage and extract files inside a PDF.
PDF Layers (OCG)
Show, hide and manage optional content layers.