📎 Free · private · in-browser
Merge PDF files into one document
Combine PDFs in any order — private, in-browser merging.
Drop PDF files here or click to choose
Merged on your device — nothing is uploaded
Combine PDFs into one clean document
Whether it’s scanned pages that arrived as separate files, a cover letter plus résumé, an invoice bundle for accounting, or chapters exported one at a time — the fix is the same: merge them into a single PDF that opens, prints, and emails as one document. This tool combines any number of PDFs in the order you choose, with page counts shown so you can verify before downloading.
How to merge PDF files
- Drop your PDFs onto the panel above — add them all at once or in batches.
- Arrange the order. Each file shows its page count; use the arrows to move files up or down. The merged document follows this exact order.
- Click Merge PDFs and download merged.pdf. Your original files are untouched.
Why in-browser merging matters for PDFs specifically
PDFs are where the sensitive documents live: contracts, tax forms, bank statements, medical records, IDs. Most online PDF sites upload your documents to their servers, hold them for “up to an hour,” and ask you to trust the deletion actually happens. FileNimbus takes the approach that the safest server is no server: the open-source pdf-lib engine runs in your browser tab, pages are copied between documents in memory, and the merged file is assembled on your own device. Close the tab and every trace is gone.
Tips for better merged documents
Merge order is easiest to get right when files sort naturally — name scans01-cover.pdf, 02-body.pdf before dropping them. Mixing page sizes (letter + A4 + receipts) is fine: each page keeps its own dimensions, though printing may rescale. If the merged file needs to be smaller for email, print-to-PDF at reduced quality in your viewer, or compress the images before generating your source PDFs — image resolution, not page count, is what makes PDFs heavy.
Frequently asked questions
Are my PDFs uploaded to a server?
No. Merging runs entirely in your browser using the open-source pdf-lib library — documents never leave your device, which makes this safe for contracts, medical records, and anything confidential.
Can I change the order of the files?
Yes — use the ↑ and ↓ buttons next to each file to arrange them before merging. Files merge top-to-bottom in the order shown.
Is there a limit on file count or size?
No hard limit. Because your own device does the work, merging dozens of large PDFs may take a few seconds; a progress note shows while pages copy.
Will bookmarks, form fields, and links survive the merge?
Page content, images, and text always survive. Interactive features (form fields, internal links, bookmarks) may be flattened or dropped depending on how the source PDF was built — check the result before deleting originals.
Can I merge password-protected PDFs?
Encrypted PDFs must be unlocked first — the browser cannot read their pages without the password. Remove the password in your PDF viewer (open + “Save as”), then merge.