VSThiran

PDF & Files

Free PDF Merger

Free to useNo sign-up requiredNo watermarkRuns in your browser

This free PDF merger combines two or more PDF files into a single document. Add your files, drag them into the order you want, and download the merged result. Each file's page count is shown as it loads, so you can check you have everything before merging.

Pages are copied across rather than re-rendered, which means text stays selectable, quality is untouched and the merged file is roughly the size of the originals added together. Your documents are read on your own device and never uploaded.

How this tool works

  1. Add two or more PDFs

    Drag them in or click to browse. Each file is opened as it is added so you can see its page count, and anything that cannot be read - an encrypted file, for instance - is flagged rather than silently breaking the merge.

  2. Put them in the right order

    Move files up or down. The merged document follows the list from top to bottom, and the running total of pages is shown as you go.

  3. Merge and download

    One click builds the combined PDF on your device and downloads it. There is no watermark and no page limit.

How it works

Every page of each file is copied into a single new document in the order you set. Pages are copied rather than re-rendered, so text stays selectable, quality is unchanged and the file size is roughly the sum of the originals.

The merged file inherits each page's original size, so mixing A4 and Letter documents produces a PDF with mixed page sizes. That is usually what you want; it prints correctly either way.

Bookmarks, form fields and digital signatures are not carried across. Signatures in particular are invalidated by merging, because the document they signed no longer exists in the same form.

Files that cannot be opened are excluded from the merge rather than aborting it, so one bad file in a batch does not cost you the whole job.

What merging preserves and what it does not

  • Preserved: page content, selectable text, embedded fonts, images, vector graphics and each page's original dimensions.
  • Not preserved: bookmarks and outlines, interactive form fields, and document-level metadata from the individual files.
  • Invalidated: digital signatures. A signature certifies a specific document, and the merged file is a different document, so sign after merging rather than before.
  • Unchanged: quality. Nothing is recompressed or re-rendered, so the merged pages are bit-for-bit equivalent in appearance.

Why merging in your browser is worth having

Most PDF mergers upload your documents to a server. For a contract, an invoice batch or a set of medical records, that means handing your files to a third party for the duration of the job.

  • Nothing leaves your device, so there is no upload wait and no server-side copy.
  • No file-size cap imposed by an upload limit - the practical ceiling is your device's memory.
  • No account, no watermark and no daily limit on how many merges you run.
  • Your files never leave your device, so there is no retention policy to read and nothing to delete afterwards.

Worked examples

A report and its appendices

Add the main document first, then each appendix in order, and download one file to send.

Scanned pages arriving separately

Drag the individual scans into page order before merging so the final document reads correctly.

Combining signed and unsigned parts

Merging invalidates existing digital signatures, so sign the merged file rather than merging signed ones.

Mixed page sizes

An A4 report merged with a Letter-size appendix keeps both sizes. Printers handle this fine, and no page is scaled or cropped.

Frequently asked questions

Is this PDF merger free?

Yes - free, with no sign-up, no watermark and no limit on the number of files or pages you merge.

Are my files uploaded to a server?

No. Your files never leave your device. The file is opened and processed by your browser on your own machine, so nothing is transmitted to VSThiran and no copy of your document is ever stored on a server.

How do I merge PDF files?

Add two or more PDFs above, drag them into the order you want, then click merge. The combined file downloads straight to your device.

Is there a limit on file size or number of files?

There is no fixed limit, but every file is held in memory while merging. Very large documents may be slow or run out of memory on a phone.

Will the quality drop?

No. Pages are copied across as they are, not re-compressed or re-rendered, so the merged document matches the originals exactly.

Can I merge password-protected PDFs?

No. Encrypted files cannot be read without the password. Remove the protection first, then merge.

Can I change the order of the files?

Yes. Move any file up or down before merging, and the merged document follows that order exactly.

Does merging keep my bookmarks and form fields?

No. Page content and text are preserved, but bookmarks, form fields and digital signatures are not carried into the merged file.