PDF Merge

Use this free online PDF Merge tool to combine any number of PDF files into a single document in your chosen order. It is useful for assembling a job application package (cover letter, CV, references), stitching together scanned receipts at tax time, consolidating multiple invoices for a client, or merging bank statements across months. Drop your PDFs into the upload zone, drag them into the order you want, and download the combined file. The merge happens in your browser using pdf-lib — your documents never leave your device, no upload limit, no watermark, no sign-up. Page-level metadata, bookmarks and form fields are preserved where possible.

Click to add or drag & drop multiple PDFs

How to Use This PDF Merge

Merging PDFs takes a drop, a drag-to-order and a click.

Drop two or more PDFs into the upload zone or click to choose multiple files.
Drag each thumbnail to set the order in which the files should appear in the merged document.
Optionally remove a file by clicking its remove icon if you change your mind.
Click Merge PDFs to combine them.
Click Download to save the combined file; the originals are untouched.

How This PDF Merge Works

PDF Merge concatenates the page streams of two or more PDFs into a single output file while preserving each page's content, fonts and embedded images. The tool uses the open-source pdf-lib library, which loads every input PDF into a structured object model in your browser, walks each PDF's page tree, and copies each page reference into a new output document in the order you set. Because the operation works at the object level rather than re-rendering pages, the merge is fast even for very large documents and the original quality is preserved exactly — no pixelation, no font substitution, no compression loss. Document-level metadata (title, author) is taken from the first input by default; page-level metadata, bookmarks and form fields are preserved where possible, although form-field naming collisions across inputs can require manual fix-up afterwards. Because the tool runs locally there is no upload limit and no risk to confidential documents — bank statements, contracts, payslips and medical records can all be merged safely. The output is a standard PDF that opens in any reader.

Last updated: May 2026.

Frequently Asked Questions

Will merging change the quality of my PDFs?

No — pages are copied exactly. Text stays searchable, images stay at full resolution.

Is there a limit to how many files I can merge?

Practically, merging dozens is fine. Browser memory is the constraint — combining a hundred 10MB files would slow things down.

Can I merge PDFs in a custom order?

Yes — use the up/down arrow buttons on each file in the list to set the order before clicking Merge.

Will form fields survive the merge?

Generally yes, but field names must be unique. If two source PDFs have identical field names, behaviour after merging may be unexpected.

Are my files uploaded anywhere?

No — pdf-lib runs entirely in your browser. Files stay local.