How to use Merge PDF
- Drop two or more PDF files on the page, or choose them from your device.
- Use the arrow buttons to put the files in the order you want the pages to appear.
- Select Merge PDFs. The merged file is built in your browser.
- Download the result. Nothing was uploaded, so there is nothing to delete afterwards.
What happens to your files
When you choose files, your browser reads them into the memory of this tab. The merge runs in a background worker inside the same tab, using pdf-lib, an open-source PDF library. The finished file is handed back to the page and saved through your browser's normal download.
At no point is a file sent to WeaveAI or anyone else. You can check this yourself: open your browser's developer tools, switch to the Network tab, and merge two files. You will see the PDF engine load once from this site, and nothing carrying your documents.
Because nothing is uploaded, there is no copy of your files anywhere to delete afterwards, and once the engine has loaded with your first merge, the tool keeps working if you go offline.
How the merged file is built
Each page is copied into the new document as it is: text stays selectable and searchable, images keep their original resolution, and web links keep working. Pages are not re-rendered or rasterised, so the merged file is roughly the size of the inputs added together.
The order of the list is the order of the pages. Use the arrow buttons next to each file to move it, or remove a file you added by mistake. Page sizes are kept per page, so you can mix A4 and US Letter in one file.
The merged file does not carry over the original files' author, title or creation dates, and it does not record when you merged it. Its producer is set to WeaveAI Tools.
When merging is the right tool
Merging suits collecting scanned receipts into one expense claim, attaching a signed page to a contract, sending a set of invoices as a single attachment, or combining chapters exported separately. If you only need some pages from a file, split or extract them first, then merge the parts you keep.
Password-protected PDFs cannot be merged until the password is removed in the application that created them. A file that is damaged or is not really a PDF is named in the error message, so you know which one to replace.
Questions
- Are my PDFs uploaded to a server?
- No. The files are read and merged by code running in your browser tab. After your first merge has loaded the engine, you can disconnect from the internet and the tool still works.
- Is there a limit on files or size?
- There is no daily limit. The practical limit is your device's memory: merging a few hundred megabytes works on most laptops.
- Are bookmarks and form fields kept?
- Pages, text, images and web links are kept exactly. Bookmarks (the outline), links that jump to another page, and interactive form fields are not carried into the merged file.
- Can I merge password-protected PDFs?
- Not yet. Remove the password first with the PDF's original application, then merge.