How to Merge, Split and Convert PDF Files Safely
PDF is the standard format for documents that need to look the same everywhere: forms, invoices, contracts, CVs, tickets and statements. Sooner or later most people need to do something with one. You might need to join several files into one upload, pull a single page out of a long report, turn phone photos into a PDF, or save a page as an image to share in a chat app. This guide explains how to do each of these jobs, what changes in the file when you do, and how to keep private documents private while you work.
Merging: combine several PDFs into one
Many online forms accept only one file, so you need to combine a CV, a cover letter and certificates, or a month of receipts, into a single PDF. A merge tool copies the pages of each file, in order, into a new document.
- Open Merge PDF and add your files.
- Put them in the order you want them to appear. The first file becomes the start of the document.
- Merge and download.
What changes: nothing on the pages. Text stays selectable and images keep their resolution. Mixed page sizes, such as A4 and US Letter, are kept as they are. What does not survive is anything that belongs to the whole original document: bookmarks, form fields spread across pages, and digital signatures. A signed contract should usually be sent as its own file, because changing it in any way invalidates the signature.
Splitting: extract, remove or reorder pages
Splitting is the opposite of merging, and it is also the easiest way to delete or reorder pages. With Split PDF you can:
- Extract pages into a new file, for example pages 3 to 5 of a report. Type
3-5. - Remove pages by extracting everything you want to keep. To drop page 6 of a 12-page file, type
1-5, 7-12. - Reorder pages by listing them in the new order, such as
2, 1, 3-10. - Cut a document into parts by range or every N pages, for example to meet an upload limit per file.
Like merging, splitting copies pages without redrawing them, so quality does not change.
Converting photos to PDF
When you photograph documents with your phone, you get a set of image files. Converting them into one PDF makes them easier to send, print and keep in order. In JPG to PDF, each image becomes a page. Choose A4 or US Letter pages for documents you may print, or "same as image" for photo collections and screenshots.
For a clean result, photograph each page flat, in good light, from directly above, and crop to the edges of the paper. If the PDF ends up too large for an email or form, use Compress PDF, and see our guide to reducing PDF file size.
Converting PDF pages to images
Some places accept images but not PDFs: social media posts, many chat apps' photo views, product listing photos and some online forms. PDF to JPG draws each page as a picture. Choose:
- JPG for smaller files and pages with photos; PNG for the sharpest text, diagrams and slides.
- 150 dpi for screens, or 300 dpi if you will print the image or need to zoom into small text.
Remember that the text in an image cannot be searched or copied, so keep the PDF as well.
Keeping private documents private
PDFs often contain sensitive information: ID numbers, addresses, bank details, signatures and medical or legal information. Many free online PDF services work by uploading your file to their servers, processing it there and letting you download the result. Reputable services delete files after a short time, but the file still leaves your device and you are relying on their policies and security.
The tools on DailyToolLab work differently. They use open-source PDF libraries that run inside your browser, so the file is read, changed and saved on your own device and is never uploaded. You can check this yourself: open your browser's developer tools, go to the Network tab and process a file. You will see the tool's code load, but no upload of your document. Whichever service you use, a few habits help:
- Prefer tools that process files locally for anything confidential.
- Do not use shared or public computers for private documents, and clear the downloads folder afterwards if you must.
- Check the result before you send it. Make sure the right pages are included and nothing extra is.
- Remember that blacking out text by drawing a box over it in a PDF editor does not always remove the text underneath. To truly redact, use a proper redaction feature, or convert the page to an image after covering the information.
Protected PDFs
Some PDFs are protected with a password, or with restrictions that block copying or editing. Browser tools, including ours, cannot merge, split or compress these until the protection is removed. If the document is yours and you know the password, open it in a PDF reader and either save a copy without security or print it to a new PDF. Never try to get around protection on documents you are not entitled to change.
Quick reference
| I want to… | Use |
|---|---|
| Combine files into one PDF | Merge PDF |
| Take out, delete or reorder pages | Split PDF |
| Make a PDF smaller | Compress PDF |
| Turn photos or scans into a PDF | JPG to PDF |
| Turn PDF pages into pictures | PDF to JPG |
All five are collected on our PDF Tools hub.
Sources
This guide is general information. Always keep an original copy of important documents, and check the file rules of the service you are uploading to. Some features mentioned belong to third-party programs; their menus can change between versions.