Merge PDF

How to merge PDF files

1. Drop your PDF files on the box above, or click Choose PDF files to pick them. You can add files in several rounds.
2. Check the list. Each file shows its page count and size. Drag a file to a new position, or use the up and down buttons, which also work on a phone and with a keyboard. Remove files you added by mistake.
3. Click Merge PDF. A progress bar shows which file is being added.
4. Click the download button. The merged file is named after the first file, for example contract-merged.pdf.

Everything happens in your browser. The files are read from your device, combined by a small JavaScript library and handed back to you as a download. Nothing is uploaded, nothing is stored, and there is no sign-up, watermark or daily limit.

How the merge works

A PDF is a container of pages, fonts and images. Merging creates a new, empty document and copies the pages of each source file into it, one file after the other, in the order of your list. The pages are copied with everything they draw, so nothing is rasterised or re-compressed. Text remains selectable and searchable, images keep their original quality, and different page sizes can sit in the same document, for example A4 pages followed by a US Letter page.

Because the content is copied as it is, the result is roughly as large as the files put together. If it is too big to email, compress it afterwards. Also note that document-level extras, such as the bookmark outline of the source files and interactive form fields, are not carried into the merged file.

Worked example

You are applying for a visa and have three files: a 4-page application form (310 KB), a 10-page bank statement (1.2 MB) and a 2-page passport scan (2.4 MB). Add them in that order and the tool lists 3 files · 16 pages · 3.9 MB. After merging you get one 16-page PDF of about the same size. If the embassy wants the passport scan first, drag it to the top of the list and merge again: the new file starts with pages 1–2 from the scan, then the form, then the statement. The original files are never modified.

Common problems

• Password-protected files. A file with a password cannot be read. Open it in a PDF viewer, enter the password and save an unprotected copy, then add that copy.
• "Could not be read". The file is damaged, was cut off during a download, or is a different format with a .pdf name. Download it again or re-export it from the original program.
• Wrong order. The order of the list is the order of the result. Check it before merging; you can reorder at any time and merge again.
• Very large files. The tool reads files into memory, so a merge of several hundred megabytes may be slow or fail on a phone. Merge in smaller groups, then merge the results.
• Scanned pages sideways. Merging keeps each page as it is. Fix rotation with a rotate tool first.

Tips for tidy documents

• Name your source files in the order you want, such as 01-cover.pdf, 02-report.pdf; the list is then easy to check.
• Merge before you sign. A signature added to separate files is not valid on the merged copy.
• Keep the originals. Merging creates a new file and leaves yours untouched, so you can always start over.
• For sensitive documents, work on a device you trust. This tool never sends data anywhere, but anyone with access to your computer can still open your downloads.

Frequently asked questions