Merge PDF files

SwiftPDFEdit's Merge PDF tool combines two or more PDF files into one continuous document, entirely inside your web browser. You add the files, put them in the order you want, and download a single merged PDF — nothing is uploaded to a server at any point.

Merging is the right tool whenever separate files really belong together as one record: a signed contract and its exhibits, a scanned batch that arrived one page per file, a report whose chapters were written by different people, or a month of receipts that has to go to accounting as one attachment. One file is easier to email, easier to archive, and impossible to send half of by mistake.

Technically the merge is a page-level copy rather than a re-render. Each page object — its text operators, embedded fonts, vector artwork and images — is copied into the output document unchanged, so the merged PDF is faithful to its sources. Nothing is rasterised: text stays selectable and searchable, and quality is identical to the originals. Expect the merged file's size to be roughly the sum of its inputs, minus a little where the same font is embedded twice.

Two limits are worth knowing before you start. A password-protected PDF has to be unlocked first, because an encrypted file cannot be read at all until it is decrypted. And an existing cryptographic signature is invalidated by any modification to a PDF, merging included — that is a property of the PDF signature standard rather than of this tool. Bookmarks and outlines defined in the source files are not carried into the merged document.

One practical tip: if the merged result is heavier than your mail server allows, compress it once at the end rather than compressing each input first — a single pass over the finished document produces a smaller and cleaner file. And because the merge happens on your own hardware, the only real ceiling on how many files you can combine is your device's available memory; dozens of ordinary documents merge without trouble.