PDF tools
Merge PDF Files Online — Combine Documents
Combine two or more PDFs into one file. Arrange the documents in order, then download a merged copy without sending your files to a server.
Input is processed locally in this browser
- 1. Choose files
- 2. Review pages
- 3. Preview & save
Choose PDFs to combine
Unencrypted PDFs without interactive forms · 25 MB total · Up to 20 files · 200 pages total
Or drop files here. File contents stay in this browser tab.
Keep your original files. These tools create a new PDF; they do not preserve digital signatures, document bookmarks or all document-level features. They do not sanitize unsafe PDFs. Only select files you trust.
How to use Merge PDF
- Choose at least two PDF files, up to 20 files and 25 MB in total.
- Move files up or down to set the document order. Each file keeps its internal page order.
- Select Merge PDFs and wait for the local processor to finish.
- Review the output preview, then download the result and check the page order before sharing it.
Combine reports, invoices or scanned chapters
For example, place a cover PDF first, a five-page report second and a two-page appendix last. The result has eight pages in that sequence. If only part of a document belongs in the combined file, extract those pages first; use Organize PDF Pages to change individual page order afterward.
File handling and limits
Processing happens in a background worker in this browser tab using pdf-lib. Files are not uploaded to Toolk. The 25 MB input limit reduces memory pressure but does not guarantee that every complex document will work on every device. Cancel a running job or try smaller files if processing takes too long.
Keep the original document. Encrypted PDFs and interactive forms are unsupported. New documents do not retain digital signatures, bookmarks, or every document-level feature. Review the output in your PDF reader before sharing. Website analytics are separate from file processing and do not receive file contents.
Frequently asked questions
Can I change the order before merging?
Yes. Use the earlier and later controls beside each filename. Pages within each input PDF stay in their original order. Use the page organizer if you need to rearrange individual pages.
Are PDF forms and signed files supported?
Interactive forms are rejected to avoid silently losing field behavior. Export a flattened copy first. A merged file does not preserve digital signatures, document bookmarks or all document-level features.
Does merging reduce the PDF file size?
This tool combines pages; it does not recompress scans or optimize images. The result may be larger or smaller than the total input size because PDF objects are rewritten.
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Last updated: September 16, 2026