Insert blank pages into a PDF
Inserting a blank page adds a new, empty page into an existing PDF without touching the original pages. This tool places blanks at the start, at the end, after a page number you choose, or after every page — the last mode is ideal for creating note-taking space beside slides or sheet music. Each blank is sized to match the page next to it, and everything runs locally in your browser.
How it works
In the PDF format, a page does not have to contain anything. The only mandatory parts of a page object are its position in the page tree and a MediaBox — the rectangle, in points (1/72 inch), that defines the page's size. A "blank page" is therefore just a page dictionary with a MediaBox and an empty (or absent) content stream: no fonts, no images, no drawing operators. That is why blanks are nearly free in file-size terms.
The interesting decision is what size the blank should be, because real documents mix sizes — a Letter report with an A3 fold-out, a scan with slightly irregular page dimensions. Rather than asking you, the tool reads the MediaBox of the neighboring page and clones its width and height: a blank inserted after page 5 matches page 5, a blank inserted at the very start matches page 1. The result never has a jarring size jump where the blank sits.
Insertion itself is an operation on the page tree, the ordered structure that gives PDF pages their sequence. Adding a blank at index i splices a new node into that structure and shifts everything after it — the original pages keep their content, annotations, and links, because none of their objects are rewritten. In after-every-page mode the tool walks the document from the last page to the first, inserting one blank behind each, so the indices of pages it has not yet processed stay valid throughout the pass.
The after-every-page mode deserves a note: it is the standard preparation for tablet annotation. Apps like GoodNotes or Xournal++ let you write anywhere, but a dedicated empty page per slide gives you unlimited writing room without covering the content — and because the blank is a real PDF page, your notes export together with the deck.
Worked example: a 30-slide lecture deck prepared for notes
A 30-page lecture PDF (16:9 slides, 3.1 MB) needs note space for a tablet. Choosing "after every page" turns it into a 60-page file: slide 1, blank, slide 2, blank, and so on, with every blank matching the slides' 960 × 540 pt dimensions. The output is 3.11 MB — the 30 blanks together added roughly 10 KB, about 0.3% of the file.
A second common case: the same student's 45-page thesis must be duplex-printed with each chapter starting on a right-hand (odd) page, but chapter 3 begins on page 18. Inserting one blank after page 17 pushes the chapter opening to page 19 — an odd page — so the printed and bound copy opens each chapter on a fresh sheet front. One 0.4 KB page fixes the whole print run.
Frequently asked questions
How do I add a blank page to an existing PDF?
Load the PDF into the tool above, pick a position — start, end, after a specific page, or after every page — and download the result. The blank is created inside the file itself, so it prints and shares like any other page.
What size will the inserted blank page be?
Each blank copies the width and height of the page it sits next to, so an A4 page gets an A4 blank and a Letter page gets a Letter blank. Mixed-size documents therefore stay consistent without any manual settings.
Can I add a blank page after every page for notes?
Yes — the after-every-page mode doubles the document by pairing each page with an empty facing page. It is designed for annotating lecture slides or scores on a tablet, where each blank becomes writing space beside the content.
Do blank pages make the PDF file much bigger?
No. A blank page is just a small dictionary with an empty content stream — typically well under one kilobyte. Even doubling a document with blanks usually adds only a few kilobytes in total.
Why would I need a blank page for duplex printing?
Duplex printers put odd pages on the front of each sheet. Inserting a blank before a chapter that must start on a front side keeps the chapter opening on the correct face of the paper.