PDF Merge
Combine multiple PDF files into one — entirely in your browser. Drag to reorder, rename the output, edit metadata. Powered by pdf-lib; nothing ever leaves your device.
Drop PDF files here
Or click to choose. Up to 50 files. Files stay on your device — they're not uploaded.
Choose PDFsWhat you'll use this for
Invoice batches
Combine a month of invoices into one PDF before sending to accounting.
Application packets
Bundle a resume, cover letter, and references in the exact order you want.
Scanned chapters
Merge chapter-by-chapter scans into a single readable document.
Forms with attachments
Append supporting docs after a signed form — no extra tools required.
How to merge PDF files
Drop in your PDFs
Drag and drop into the file zone, or click to browse. Add more anytime — the queue grows.
Drag to reorder
Each card has a grab handle on the left. Reorder by dragging, or use the up/down arrows. Page order inside each PDF is preserved.
Set filename and metadata
Choose an output filename, and optionally a PDF title and author. These appear in the final document's metadata.
Click Merge & download
The merged PDF is generated locally and offered as a download. Nothing is uploaded.
Frequently asked questions
No. Merging happens entirely in your browser via pdf-lib. The file bytes never leave your device.
The tool accepts up to 50 files. Total size is limited only by your browser's memory; ~500 MB is comfortable on a modern desktop. If you hit memory issues, merge in smaller batches.
Yes — drag a card to reorder, or use the up/down buttons. The order of pages inside each PDF is preserved.
No. The output is a plain merged PDF — no watermarks, no logos, no tracking.
Encrypted PDFs are not supported and will be skipped with an error. Remove the password using your PDF reader first, then merge.
About PDF merging
PDF merging is conceptually simple: take all the pages from each input file and stitch them into a new document. The hard parts — preserving fonts, images, annotations, form fields, and outlines — are handled by pdf-lib, an MIT-licensed PDF toolkit that runs entirely in the browser using WebAssembly for parsing.
What is preserved
- Original page sizes, rotations, and content streams
- Embedded fonts and images (deduplicated where possible)
- Hyperlinks and annotations inside page content
- Per-page metadata, including bookmarks where present
What changes
- Top-level document metadata is replaced with your title/author/producer values.
- Outline (bookmark) structure is regenerated from the input documents.
- Form fields with conflicting names across PDFs are renamed to avoid collisions.