PDF Tools

How to Split a Scanned Two-Page Spread in Half

The problem of two pages ending up on one sheet in book and magazine scans: choosing vertical or horizontal splitting, where the cut line falls, skewed scans, and page order after splitting.

Extract Pages, Split a PDF, or Delete Pages? Choosing the Right Tool

Three different ways to separate pages from a PDF compared: extraction, splitting, and deleting with an organizer. Which gives the right result in fewer steps in each scenario.

How to Optimize a PDF for the Web (Linearize)

Restructuring a PDF for fast web view: what linearization is, who benefits, its effect on file size, and how it differs from compression.

How to Add Text and Shapes to a PDF

Editing PDFs in the browser: adding text boxes, drawing, placing a signature, font and positioning settings, and the checks to make before saving.

How to Extract Pages from a PDF: A Range Selection Guide

The steps for extracting specific pages as a new PDF: writing ranges, cover page offset, selecting multiple ranges, and what's preserved and lost in the extracted file.

How Does PDF Page Extraction Work? The Object Tree and Shared Resources

The background of page extraction: PDF's page tree structure, shared resources, why the extracted file can stay large, and what happens to bookmarks and links.

What Is a PDF Overlay? Content Streams and Layer Logic

What the overlay operation corresponds to inside the file: XObject form objects, appending to the content stream, drawing order, transparency groups, and how resource collisions are resolved.

Editing a PDF: A Browser Tool, a Desktop Program, or Converting to Word?

Three ways to change a PDF compared: browser-based layer adding, desktop PDF editors, and converting to Word and saving back. Which is right for which job.

Why Isn't Editing a PDF Like Editing in Word? The Format's Technical Logic

Why text can't be edited in place in a PDF, how page content is stored, the difference between adding a layer and real editing, and the limits of browser-based editors.

How to Add a Letterhead or Stamp with PDF Overlay

Overlaying one PDF onto another: applying letterhead paper, stamping, page alignment, size mismatches, and deciding between background and foreground layering.

Ways to Add a Letterhead: Overlay, Watermark, or a Word Template?

Three methods for adding a corporate letterhead, logo or stamp to a PDF compared: an overlay tool, a watermark tool, and using a template in the source document.

N-up: How to Combine Multiple PDF Pages onto One Sheet

2-up, 4-up and 6-up layouts: how many pages fit on a sheet, the legibility limit, choosing landscape or portrait orientation, and the paper-saving math.

What Is N-up? The Logic of Page Imposition and the Scaling Math

The background of the N-up operation: how the scale factor is calculated, what happens when aspect ratios don't match, the difference between N-up and booklet layout, and the effect on file size.

An N-up Tool or a Printer Setting? Ways to Put Multiple Pages on One Sheet

Converting a PDF into an N-up file compared with using your printer driver's 'pages per sheet' setting. Differences in control, shareability and print quality.

What Is a Linearized PDF? The Technical Background of Fast Web View

PDF's xref structure, hint tables, byte-range requests, and how a linearized file structurally differs from a normal one — why the first page arrives faster.

PDF Speed on the Web: Linearize, Compress, or Split?

Three ways to speed up the large PDFs on your site compared: linearization, compression and splitting the file into parts. How much each one actually gains you.

The Two-Page Spread Problem in Book Scans: Why It Happens and What to Do

The technical reason two pages end up on one sheet in scanned books, how crop boxes (MediaBox/CropBox) work, and what splitting actually changes inside the file.

Split the Spread, Rescan, or Just Crop? Which Makes More Sense

Three ways to fix scanned book PDFs compared: splitting in half with software, rescanning the book, and getting by with cropping alone. Differences in time, quality and outcome.

Extracting Images from a PDF: Which Method Works Best, and When?

Extracting images from a PDF: which method makes sense when? A comparison of screenshots, manual copying, and automatic extraction tools.

Extracting Images from a PDF: A Guide to Lossless Extraction of Embedded Pictures

How to extract the images inside a PDF as separate files at their original quality, common use cases, and what you should know about privacy.

Extracting Images from a PDF: A Step-by-Step Practical Guide

How to extract the images inside a PDF as separate files with full quality and speed, explained step by step, along with common mistakes to avoid.

How Does PDF Compression Work? A Guide to Shrinking Files Without Losing Quality

A guide explaining how PDF compression tools work, what technology they use, and when they actually help.

PDF Compression: By Hand, Desktop Software, or an Online Tool?

We compared online compression, desktop software, and manual methods for shrinking PDF file size. Here's an unbiased look at which one makes sense in which situation.

Organizing PDF Pages vs. Rebuilding From Scratch: Choosing the Right Method

Which approach makes more sense when you need to reorder or delete PDF pages? An unbiased comparison of the page-organizing tool against alternative solutions.

Organizing PDF Pages: A Step-by-Step Guide to Reordering and Deleting

A practical, step-by-step guide to reordering, deleting, and rearranging PDF pages.

How to Add Page Numbers to a PDF: A Step-by-Step Guide

A step-by-step guide to adding page numbers to PDF files, including position, format, and starting-number options, plus common mistakes to avoid.

Adding Page Numbers to a PDF: Why This Simple-Looking Task Isn't Actually Simple

A comprehensive guide to the technical details behind adding page numbers to PDFs, position/format options, when you actually need it, and what happens to your file's security.

Adding Page Numbers to a PDF: Which Method Makes Sense, and When?

An unbiased guide comparing when adding page numbers to a PDF is necessary, and which method — desktop software, an office program, or an online tool — makes more sense in which scenario.

Rotating PDF Pages: When and How Should You Do It?

Why does rotating PDF pages by 90, 180, or 270 degrees become necessary, how do browser-based tools work, and is your file safe? A detailed guide.

How to Rotate PDF Pages: A Step-by-Step Guide

How do you rotate PDF pages by 90, 180, or 270 degrees? A step-by-step, browser-based method for fixing sideways-scanned documents.

Rotating PDF Pages: Which Method Should You Use, and When?

We compared online tools, desktop software, and manual methods for rotating PDF pages. Here's which one makes more sense in which scenario, with examples.

How to Split a PDF: Guide to Separating by Page or Page Range

How do you split a PDF into page ranges or individual pages? A step-by-step guide with practical tips and common mistakes.

How to Crop a PDF: A Guide to Trimming Page Margins

Learn how to trim excess white margins from PDF pages step by step. Content is never deleted — only the visible area is reduced.

Crop PDF: Narrowing Margins Without Losing Content

A guide to the tool for cropping unnecessary margins in PDF pages without content loss — its method, use cases, and approach to privacy.

Cropping PDF Margins: Which Method Makes Sense When?

A comparison of online tools, desktop software, and print settings for cropping blank margins in PDF pages; which one suits which scenario.

How to Compare PDFs: A Guide to Finding Differences Page by Page

A step-by-step guide to finding text and visual differences between two PDFs page by page and downloading the result as a ZIP report.

How Does PDF Comparison Work? Behind the Scenes of Page-by-Page Diff Detection

Explains how the PDF Compare tool finds differences between two PDFs page by page, at both the visual and text level, when it's useful, and its approach to privacy.

How to Add a Watermark to a PDF: Easy Step-by-Step Guide

A step-by-step guide for anyone who wants to add a text watermark to their PDF file. Transparency, angle settings, and common mistakes, all covered here.

Adding a Watermark to a PDF: When to Automate It, When to Do It by Hand

We compared online tools, desktop software, and manual methods for adding watermarks to PDFs. Which one makes sense in which scenario, explained step by step.

Adding a Watermark to a PDF: What It Does and How It Works

A comprehensive guide to the logic behind adding text watermarks to PDF files, the technology involved, the security angle, and practical use cases.

How to Reduce PDF Size: A Step-by-Step Compression Guide

Learn how to shrink PDF files without sacrificing quality. A step-by-step compression guide, practical tips, and common mistakes to avoid.

Splitting PDFs: When Should You Do It Manually, and When Should You Use a Tool?

We compared manual methods, desktop programs, and online tools for splitting PDFs. We explain, objectively, which one makes sense in which scenario.

Split PDF: A Guide to Dividing Documents Page by Page or by Range

What does a PDF split tool do, how does it work, and is your data safe? A guide to selecting page ranges, splitting into individual pages, and choosing the right method.

Merging PDFs: Browser or Desktop Software? A Comparison Guide

We compared browser-based tools, desktop programs, and manual methods for merging PDFs. We explain, with examples, which one makes sense in which scenario.

How to Merge PDF Files: A Step-by-Step Guide

A step-by-step, browser-based, and secure guide to merging PDF files into a single document in the right order.

How PDF Merging Works: Combining Files In-Browser with WASM, Without Ever Touching a Server

How does a PDF merge tool actually work, what is WASM technology for, and why are your files merged without ever being uploaded to a server? A detailed guide.

Organizing PDF Pages: How Do Reordering and Deleting Work?

An explanation of how the organize-pdf page-reordering and page-deletion tool works, when it's useful, and what it means for your privacy.

Finding the Difference Between Two PDFs: Which Method Works When?

An unbiased guide comparing when the Compare PDF tool works best against manual methods and general-purpose online tools.

PDF Won't Open? A Guide to Choosing the Right Repair Method

Comparing ways to repair corrupted PDF files: when do online repair tools, desktop programs, and manual methods actually work?

Is Your PDF File Not Opening? The Technical Way to Repair Corrupted PDFs

How to repair corrupted or unopenable PDF files: an explanation of xref table and trailer errors and how they're fixed.

How to Repair a Corrupted PDF? A Step-by-Step Practical Guide

Repairing a corrupted or unopenable PDF file: a step-by-step guide to fixing xref and trailer errors.

What Is Bates Numbering? A Guide to Sequential Numbering for Legal Documents

What is Bates numbering, why is it used in legal documents, and how do online tools apply it securely? A comprehensive explainer guide.

How to Do Bates Numbering: A Step-by-Step Guide for Legal Documents

Learn how to add Bates numbers to legal documents step by step: choosing a format, using a prefix, ordering multiple PDFs, and common mistakes.

Bates Numbering: By Hand, Desktop Software, or an Online Tool?

We compare manual marking, desktop software, and online tools for Bates numbering. An honest look at which approach makes sense in which scenario.