Merge PDF Files Online – Combine Multiple PDFs into One

Combine two or more PDF files into a single document instantly. Free, no registration required, and your files never leave your device.

How to Merge PDF Files Online

  1. 1
    Select your PDF files

    Click the upload area and select two or more PDFs from your device. You can also drag and drop multiple files at once.

  2. 2
    Files are merged automatically

    AllInOnePDF combines your PDFs in the upload order. All pages, fonts, and images are preserved exactly as in the originals.

  3. 3
    Download the merged PDF

    Click "Download Result" to save your single combined PDF file.

When Should You Merge PDFs?

Reports and proposals

Combine a cover page, body, and appendix into one professional document for clients or stakeholders.

Contracts and agreements

Merge signed signature pages back into the main contract to create one complete legal document.

Portfolios

Combine work samples, case studies, and a CV into a single portfolio PDF for job applications.

Scanned documents

Join multiple scanned pages exported as separate PDFs into a single, easy-to-share document.

Frequently Asked Questions

How do I merge multiple PDF files into one?+

Upload two or more PDF files using the upload area above. AllInOnePDF will automatically combine them in the order you selected and let you download the merged file.

Is there a limit to how many PDFs I can merge?+

You can merge as many PDFs as you like. Each individual file must be under 50 MB. There is no limit on the total number of pages in the merged document.

Will merging PDFs change the formatting or fonts?+

No. AllInOnePDF copies pages directly from each source PDF into the merged document. Fonts, images, layouts, and page sizes are preserved exactly as they appear in the originals.

Can I reorder the PDFs before merging?+

The pages appear in the order the files are selected for upload. To control the order, select the files in the sequence you want them to appear in the merged output.

Can I merge PDFs of different page sizes?+

Yes. AllInOnePDF handles mixed page sizes (A4, Letter, custom). Each page in the merged PDF retains its original dimensions.

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