What does PDF Merge do?
It creates one new PDF that contains every page from the selected files in the order shown in the list.
Add supported PDFs, arrange the list, name the output, and download one combined file.
Preparing the editor...
The guide and instructions on this page are available while the tool loads.
PDF Merge builds one PDF from every page in 2 to 25 source files. The combined document follows the left-to-right, top-to-bottom order of the file cards you arrange before starting.
Add PDFs in one or more uploads, remove any card you do not need, and reorder whole files by dragging or using the up and down arrows. First-page previews help you recognize each file, but they are not a page-level editor. Pages inside each source PDF stay in their existing sequence.
The helper copies pages into a new pdf-lib document without intentionally rasterizing text or graphics. Mixed A4, Letter, portrait, landscape, and already-rotated pages keep their existing dimensions and orientation. Document-level bookmarks, named destinations, attachments, and source metadata are not transferred into the new file, and interactive links, forms, annotations, and layers should be checked in the download.
All merge work stays in the browser. Ordinary site assets may still load, and usage metadata such as counts, byte totals, page totals, and result codes may be recorded. Identified events omit filenames, raw PDF contents, and document text.
Each file can be up to 50 MB, and the selected set can total up to 200 MB. Encrypted PDFs are rejected because there is no password field. Creating the new document invalidates certificate-based signatures from the sources. Progress is shown while reading and combining files, but there is no dedicated cancel control once work has started. Large selections can strain browser memory on desktop or mobile.
Typical tasks this tool is built for.
PDF merging runs locally in your browser with pdf-lib. Selected PDF bytes are not uploaded to DevToolKit for merging. Usage and diagnostic metadata such as file count, input and output byte totals, combined page count, page context, engine label, and result or error codes may still be sent; identified PDF Merge analytics do not include filenames, raw PDF bytes, document text, or passwords.
Practical tips before you download or share the output.
Requires at least 2 PDFs and accepts up to 25. Each file can be up to 50 MB, and the combined selection can reach 200 MB. Only PDF files are accepted. Ordering applies to whole files through drag-and-drop or arrow buttons; there is no page-range picker, page reorder, page delete, or rotation step during merge. Duplicate selections are allowed. Mixed page sizes and orientations remain. Pages are copied with pdf-lib rather than intentionally rasterized. Bookmarks, named destinations, attachments, encryption, and source metadata are not carried into the new PDF. Link, form, annotation, and layer behavior should be verified after download. Encrypted input must be unlocked first. Certificate signatures from the sources do not remain valid on the merged file. Default output name is merged.pdf and can be edited. Automatic and manual download are available. Reset clears the workspace; it does not provide a true mid-merge abort.
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Common next steps after using this tool.
Reduce one PDF using JPEG page rasterization or a non-raster structure repack, then download a separate -compressed.pdf.
Encrypt one PDF with a required open password, optional owner password, and viewer permission presets or custom print, copy, edit, and annotate controls.
Build an editable DOCX from the PDF text layer, with optional Page N headings and best-effort Word tables.
Turn PDF text into an editable XLSX workbook with page sheets, detected-table sheets, or one combined data sheet.
Recognize printed text on scanned or image-based PDF pages locally, then export a TXT or Markdown working copy for proofreading.
Select pages and ranges from one PDF and copy them into one new extracted PDF downloaded directly.
Situations where this workflow saves time.
It creates one new PDF that contains every page from the selected files in the order shown in the list.
At least two valid PDFs are required before merging can start.
Up to 25 PDFs can be included in one merge.
Each PDF can be up to 50 MB.
Yes. The selected files together can total up to 200 MB.
Yes. Drag whole-file cards or use the up and down arrow buttons. The merged PDF follows that list from first to last.
No. Every page from a source file is copied in its existing internal order.
No. This tool merges complete files. Use Extract or Split when you need page ranges first.
Yes. Duplicates are not removed automatically, so the same file can contribute its pages more than once.
Yes. Mixed sizes and orientations remain as they are. The merger does not normalize, crop, or center pages.
No intentional rasterization occurs. pdf-lib copies pages into a newly created document.
There is no dedicated abort control. Resetting the workspace can discard pending UI results, but it may not stop pdf-lib work already running in the browser.
Preservation of every page-level link and annotation has not been verified. Test important interactive content in the merged result.
Interactive form behavior is not guaranteed after pages are copied into a new PDF. Check filled forms carefully.
No. Source bookmarks, outlines, and named destinations are not copied into the newly created merged document.
No. There is no password field, and encrypted files are rejected. Unlock an authorized copy first.
No. PDF Merge does not decrypt files. Use PDF Unlock when you already know the password.
The output is a new PDF, so certificate-based signatures from the sources do not remain valid on the merged document. Keep the signed originals.
Source document-level metadata is not copied into the new merged PDF. Inspect the output if title, author, or similar fields matter.
Local. Page copying runs in the browser with pdf-lib. There is no merge upload API for the PDF bytes.
PDF bytes are not uploaded for merging. Identified analytics may include file count, byte totals, page count, path or referrer context, and result codes, but not filenames, raw PDF contents, or document text.
The default is merged.pdf. You can edit the name before merging; the tool sanitizes it and ensures a .pdf extension.
Browse related tools or open the full workspace.