How to merge, split and reorder PDF pages

By the LambiPdf team · Updated 1 November 2026 · 6 min read

A visa application wants one PDF with your passport, a bank letter and three payslips. A scanner produced forty pages, two of them upside down. A 200-page report needs to go out as separate chapters. These are the everyday page-organizing jobs, and they all happen in the same place.

Combine files into one PDF

1. Open Merge PDF and add all your files at once. You can drop PDFs and images (JPG, PNG) together; each image becomes a page.
2. Drag pages, not just files, into order. You can put page 3 of one document between two pages of another.
3. Save. The combined PDF is created in your browser and downloaded.

Tip: name your files with a number prefix, such as 01-passport, 02-bank-letter, before adding them, so they start in roughly the right order.

Fix sideways and upside-down pages

Scanners and phone apps often save landscape pages or flipped sheets the wrong way round. In the page view, rotate just the pages that need it with Rotate PDF, rather than the whole document. Rotation is stored in the file, so the page opens the right way in every reader.

Remove and add pages

• Delete blank pages, duplicate scans and pages the recipient doesn’t need with Delete pages. It also makes the file smaller.
• Duplicate a page when a form needs the same sheet twice.
• Insert a blank page to keep double-sided printing aligned, so every chapter starts on a right-hand page.

Split a long PDF

Split PDF breaks a document into smaller files. Common ways to split:

• Every page separately, for example to file individual invoices from one scan.
• Custom ranges such as 1–12, 13–30 and 31–end, for chapters or sections.

If you only need a few pages, use Extract pages to pick them and save them as one new PDF.

Finishing touches

• Add page numbers after merging, so the numbering runs through the combined document.
• Check the document title in the metadata. Readers show it in the window title, and a merged file may still carry the first file’s title.
• If the result is too big to email, see how to compress a PDF for email.

Undo is your friend

LambiPdf keeps an undo and redo history while you work, and your original files are never changed. Your edits only become a new file when you save, so you can experiment with the order freely. Everything runs in your browser, so documents like passports and payslips stay on your device.

Questions people ask