FreeNo uploadNo sign-upBatch
Merge PDF Files
Combine PDFs and images into one document, in the order you choose. Your files stay on your device.
Drop PDFs or images to combine
batch and mixed formats welcome
- Private by design. Converted inside your browser.
- Instant. No upload queue, no waiting.
- Unlimited. Convert hundreds of files, download as ZIP.
How to merge PDF files
Add your files
Drop PDFs, or mix in JPG, PNG and HEIC images. Each image becomes a page.
Arrange the order
Use the arrows next to each file to move it up or down. The page numbers update as you go.
Download the merged PDF
The combined document is built instantly. Click Download merged PDF to save it.
Combine documents without uploading them
Merging is one of the most common PDF jobs: a contract and its appendices, a set of invoices for an expense claim, scanned pages that came out as separate files, or a cover letter plus CV for a job application.
Most merge tools upload your documents to a server. Here the pages are copied into a new PDF directly in your browser. They are copied as they are, not re-rendered, so text stays selectable and searchable and quality does not change.
Frequently asked questions
Is merging PDFs here safe for confidential documents?
Yes. The files are combined inside your browser and are never uploaded, so nobody else can access them.
Does merging reduce quality?
No. Pages are copied without re-rendering or recompression. Text remains selectable and images keep their original quality.
Can I merge images and PDFs together?
Yes. JPG, PNG, WebP, HEIC and other images are added as pages alongside your PDF pages.
How many files can I merge?
There is no fixed limit on files or pages. Very large documents are limited only by your device’s memory.
Are my files uploaded to a server?
No. formatmath converts files with code that runs inside your browser. Your files are never uploaded, stored or seen by us.
Is it free?
Yes. There is no watermark and no daily limit. An account is optional and only keeps a history of your conversions.