Resources
Reference articles about the PDF format and privacy. Written to help you understand what is inside your PDFs and how to handle them safely — without uploading anything.
22 articles in 4 categories
7 articles
PDF Basics
How the PDF format works: structure, file size, page sizes, and compression.
What Is a PDF? Format Basics Explained
A plain-language introduction to the PDF format: history, internal structure, versions, and why it became universal.
Read →PDF File Size: What Makes PDFs Large?
The four main factors that drive PDF size — images, fonts, scanned pages, and repeated objects.
Read →PDF Page Sizes: A4, Letter, and More
A reference to page size standards: the ISO 216 A-series and North American Letter and Legal.
Read →PDF Compression Explained
How PDF compression works: lossy vs lossless, image codecs, font subsetting, and object streams.
Read →PDF Compression vs. ZIP: Which Actually Reduces File Size?
Why zipping a PDF barely shrinks it, how PDF compression works inside the container, and when ZIP is still useful.
Read →PDF Versions Explained: 1.4, 1.7, 2.0, and PDF/A
A reference to PDF versions 1.4 through 2.0 and the PDF/A, PDF/X, and PDF/UA subsets — what each version added and when to use which.
Read →PDF vs XPS vs EPUB: Which Format to Use?
Honest comparison of PDF, XPS, and EPUB — what each format is for, where each wins and loses, and which to pick for your document.
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6 articles
Privacy
Why local-first processing matters, what your metadata leaks, and how to handle PDFs safely.
Why Local PDF Processing Matters
The case for processing PDFs locally: upload risks, compliance, trust, and what local-first changes.
Read →What Your PDF Metadata Reveals
PDF metadata can reveal the author, creation tool, timestamps, and edit history. Learn what leaks and how to remove it.
Read →Safe PDF Handling: A Practical Guide
Low-effort habits for handling PDFs safely: check sources, process locally, strip metadata, watch for permissions.
Read →PDF Security Explained: Passwords, Permissions, and Encryption
How PDF security works: user vs owner passwords, permission flags, RC4 vs AES encryption, and the honest limitations of PDF protection.
Read →Free PDF Tools Without Uploading (Your Files Stay Local)
A hub of PDF tools that process files in your browser — no upload, no server, no account. How local-first, private PDF tools work and why they simplify GDPR and CCPA compliance.
Read →Browser PDF Editor: Edit PDFs Without Installing Anything
What a browser PDF editor can and cannot do — structural edits yes, visual text editing no, and why the line is where it is.
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4 articles
Reference
Deep technical explainers on PDF internals: encryption, accessibility, and standards.
PDF Encryption Explained: RC4 vs AES-128 vs AES-256
How PDF encryption works: RC4 (deprecated), AES-128 (PDF 1.5), and AES-256 (PDF 1.6). Which to choose and why RC4 is broken.
Read →PDF/UA Explained: What Makes a PDF Accessible
PDF/UA (ISO 14289) is the standard for accessible PDFs. What it requires — tagged PDF, reading order, alt text, document language — and why it matters.
Read →Client-Side PDF Processing: How Browser-Local PDF Tools Work
Technical explainer: how IXPDF uses Web Workers, pdf-lib, PDF.js, and WASM to process PDFs in the browser with no server roundtrip. For developers and IT admins.
Read →How PDFs Store Text and Images (Under the Hood)
Technical explainer of the PDF file structure: objects, xref table, trailer, streams, and how text, fonts, and images are encoded inside a PDF.
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5 articles
Comparisons
Honest comparisons of IXPDF with other PDF tools — privacy, features, limits, and pricing.
IXPDF vs iLovePDF: Private, No Limits, No Signup
Honest comparison of IXPDF (local-first, no upload) and iLovePDF (upload-based, mature, more tools). Privacy vs features — pick the right tool for your file.
Read →IXPDF vs Smallpdf: Free Forever, No Upload
Honest comparison of IXPDF (local-first, no upload, no account) and Smallpdf (upload-based, freemium, Pro features, API). Privacy vs features.
Read →IXPDF vs PDF24: Browser-Local vs Desktop App
Honest comparison of IXPDF (browser-local, no install, no upload) and PDF24 (free desktop app, more tools, OCR). Install vs browser, and tool breadth.
Read →IXPDF vs Adobe Acrobat: Free Online PDF Tools Comparison
Honest comparison of IXPDF (free, local-first, no install, no upload) and Adobe Acrobat (paid, full-featured, OCR, digital signatures). Cost, privacy, features — pick the right tool for your file.
Read →IXPDF vs WPS Office: Free PDF Tools Comparison
Honest comparison of IXPDF (free, local-first, no install, no upload) and WPS Office (freemium desktop office suite, PDF editor, offline). Cost, privacy, features — pick the right tool for your file.
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Tools
Put it into practice
Every concept above can be tried on a real file with ourPDF tools. Compress, merge, split, convert, rotate, watermark, and edit metadata — all locally in your browser. Your files never leave your device.