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Practical guides on PDF tools, image formats, browser security, and why keeping files local matters.

PDFPrivacy 8 min read

How to Merge PDFs Without Uploading Them

Most online PDF mergers upload your files to a server — including contracts, invoices, and confidential documents. Here is how to do it entirely in your browser.

PrivacyPDF 7 min read

Why Your PDF Tools Shouldn't Be Uploading Your Files

Every time you use an online PDF tool, your document may be stored on a third-party server for days. Here is what actually happens and what to use instead.

PDF 7 min read

Compressing PDFs: File Size vs. Quality Explained

Why PDFs can be surprisingly large, what compression actually removes, and how to choose a target size without making your document unreadable.

PDFImages 6 min read

PDF to JPG: When (and When Not) to Convert

Converting a PDF to images loses text selectability, searchability, and copy-paste. Here is when the trade-off is worth making and when to keep the PDF.

ImagesiPhone 6 min read

HEIC to JPG: The iPhone Photo Problem and How to Fix It

Since iOS 11, iPhones save photos in HEIC format. Windows cannot open them, most websites reject them, and email clients show a blank file. Here is the fix.

Images 8 min read

Image Compression Formats Compared: JPG vs WebP vs AVIF in 2026

Which format gives the best quality at the smallest file size? A practical comparison of JPG, WebP, and AVIF with real numbers and browser support data.

Technical 8 min read

How Browser-Based File Tools Actually Work (WebAssembly Explained)

WebAssembly lets your browser run near-native code for tasks like PDF processing and image compression. A plain-English explanation of what is happening under the hood.

PrivacyPDF 7 min read

PDF Privacy: What Happens to Files on Free Online Tools

Free PDF tools have to make money somehow. When you upload a document, where does it go, how long is it kept, and who can access it? We investigated.

PDF 6 min read

How to Remove Pages from a PDF Without Uploading

Three ways to delete pages from a PDF — including a fully browser-based method that never uploads your file to any server.

PDF 5 min read

How to Add Page Numbers to a PDF

A practical guide to numbering PDF pages — using browser tools, desktop software, and Word — with notes on which approach preserves your file's privacy.

PDF 7 min read

How to Compress a PDF for Email Attachments

Most email providers cap attachments at 10–25 MB. Here is how to reduce a PDF's file size — from quick browser-based options to server-side tools for image-heavy documents.

PDF 6 min read

How to Extract Text from a PDF

Copy, paste, or download text from any PDF — including options that work without uploading your file to a server. Plus why scanned PDFs are different and what to do about them.