Merge PDF Files – Free Online Tool
Combine multiple PDF files into one. Merge PDFs quickly and easily in your browser.
Example Output
Real merged PDF (not a ZIP). Drag-and-drop reordering, optional bookmark generation per source file, and metadata from the first PDF by default.
application.pdf — 35 pages in chosen order, all bookmarks and metadata preserved
What is Merge PDF Files?
Combine multiple PDF files into a single document with drag-and-drop ordering, no file-count limit, and zero quality loss. Each source contributes its real pages — no re-rendering, no compression — so a merged PDF is byte-for-byte equivalent to the originals stitched together. Optional bookmarks make navigation easy.
Why use this tool?
- Works offline after the first page load
- Lightweight page weight that loads quickly even on slow connections
- Works on desktop, tablet, and mobile in any modern browser
- Built on SheetJS / pdf.js / OOXML — the same libraries used by serious desktop tools
- Auto-detects encoding (UTF-8, Shift_JIS, GBK, Vietnamese) for CSV imports
How to use
- Upload multiple PDF files
- Arrange files in order
- Click "Merge PDFs" button
- Download the combined PDF
Examples
Job application bundle
Resume + cover letter + 3 work samples + 2 reference letters merge into one `application.pdf` for a single upload.
Legal exhibit binder
Twenty-five exhibits combine into one PDF with bookmarks named after each source — judge can navigate to any exhibit instantly.
Scanned-paper archive
Daily scans throughout a month merge into one monthly archive PDF for clean filing.
Common use cases
- Submitting multi-document applications (jobs, grants, admissions)
- Building legal exhibit binders
- Archiving daily/weekly scans as a single file
- Combining chapters or reports from multiple authors
- Producing single-PDF deliverables for clients
Troubleshooting
- Output file is huge
- Sources were already large. Run the merged file through a PDF compressor afterwards. The merger doesn't re-encode (by design) so it can't shrink the source pages.
- Bookmarks missing
- Source PDFs without internal bookmarks contribute nothing. Toggle "create one bookmark per source file" so each file gets a top-level bookmark labelled with its filename.
- Form fields stop working after merge
- Two sources used the same field names — the merge flattens duplicates. Rename fields uniquely in each source PDF, or flatten the fields before merging.
Frequently Asked Questions
Up to 20+ files in one operation depending on size. Total memory matters more than file count — combining a few large PDFs may be slower than many small ones.
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