Merge PDF

How Merge PDF combines your files

The tool opens each PDF in your browser, copies its pages in sequence into a new document, and saves that document as a single download. The source files are read, never modified, so you can always start again from the originals.

Pages are copied with their own size and orientation. A Letter page stays Letter and an A3 drawing stays A3; nothing is rescaled to a common size. Text that was selectable remains selectable, and images keep their original quality because they are copied rather than re-encoded.

Plan the order before you upload

The order of files in the list is the order of pages in the result. Spending a minute on the sequence avoids rebuilding the document later.

• For a job application: cover letter, CV, then certificates in the order the advert lists them.
• For an expense claim: the claim form first, then receipts in date order, so the reviewer can tick them off line by line.
• For a report: title page, executive summary, main body, appendices. Merge the appendices last so their numbering stays meaningful.
• Give files a numeric prefix such as 01-cover.pdf and 02-cv.pdf before choosing them. Most file pickers sort by name, so the list starts close to the right order.

How to merge PDF files

1. Open Merge PDF and choose two or more PDF files.
2. Check the file list and rearrange items until it matches your planned order.
3. Start the merge. A progress indicator shows each document being copied.
4. Download the combined PDF and open it. Use your viewer's thumbnail panel to confirm the sequence at a glance.
5. If a page is in the wrong place, fix it in Reorder PDF rather than merging again from scratch.

Common problems and their fixes

A worked example

A freelancer needs to submit a monthly invoice pack: a two-page invoice exported from accounting software, a one-page timesheet from a spreadsheet, and five photographed receipts already converted with JPG to PDF. Named 01-invoice, 02-timesheet and 03-receipts, the files load in the right order. The merged result is an eight-page PDF where page 1 is the invoice total, page 3 the timesheet and pages 4 to 8 the receipts, which matches how a client's accounts team checks a claim.

Because the receipts were photographed, they make up most of the file size. If the client's portal caps uploads at 5 MB, the efficient fix is to rebuild only the receipt PDF at a lower image quality, then merge again, rather than trying to shrink the whole pack afterwards.

Merging versus attaching separate files

One combined PDF is easier to review, archive and print, and it cannot arrive incomplete. Separate files are better when different people need different documents, when one part will change frequently, or when a system expects each document as its own upload. If a recipient asks for "one PDF", merge; if a form has separate upload fields, respect them.

Merging also does not combine security settings. If any part of the pack is confidential, merge first and then apply Protect PDF to the final file, so a single password covers the whole document.

Privacy

Merge PDF runs in your browser tab. The documents are read from your device, combined in memory and handed back as a download. Closing or refreshing the page discards the working copy.

Before you send the merged file

• Check the total page count against the sum of the source documents. A missing page usually means one source failed to load or was selected twice.
• Look at the first page of each original document inside the merged file; that is where order mistakes show up.
• Rename the download to something the recipient will recognise, such as 2026-10-expenses-jsmith.pdf, rather than a generic name.
• If the document will be printed double-sided, consider adding a blank page after any source with an odd number of pages so each new section starts on a fresh sheet.