Privacy-first
Merge confidential PDFs
Merging confidential documents — contracts, financial records, legal files — requires a tool that keeps them private. PDFWhisk merges PDFs locally in your browser: nothing is uploaded to any external server. Add your files, drag to set the order, and download a single merged PDF. No account needed, no cloud storage, no server access to your documents.
At a glance
- Use this page to merge files quickly with a guided workflow.
- Accepted input: .pdf.
- Output: downloadable files generated in-browser for supported workflows.
- Upload Choose your file
- Process Runs locally
- Download Save result
Drop your files here
or tap to browse · accepts .pdf
Runs in your browser. No file uploads for supported tools.
Best on desktop for 100MB+ files · mobile recommended under ~100MB.
How local processing works
- Your PDF is processed in your browser using local JavaScript libraries.
- PDFWhisk does not upload your file to a processing server for supported tools.
- Only normal page assets load from the site (HTML/CSS/JS), not your document contents.
Selected files
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Support: contact form (reply in ~24h)
Security & privacy detailsHow this tool helps
Combine multiple PDF documents into a single file in seconds. Simply drag and drop your PDFs, arrange them in the order you want, and merge. Our tool preserves all formatting, bookmarks, and links from the original documents. Perfect for combining reports, contracts, invoices, or any documents that need to be in one file. Reorder pages by dragging them into position before merging. All processing happens in your browser - your sensitive documents never touch our servers. Merges up to 10 PDFs at a time on the free plan (more with Pro) and produces a clean, properly structured output document. Use it when you need to merge PDFs on iPhone, compress after merging, split a merged file later.
Best for
How it works
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1
Open PDFWhisk Merge tool
Visit PDFWhisk in your browser and open the Merge PDF tool. Works on desktop and mobile — no app or account needed.
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2
Add your PDF files
Drag multiple PDF files onto the page, or click to select them. Your files stay on your device — nothing is uploaded.
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3
Reorder if needed
Drag the file thumbnails to arrange them in the order you want in the merged document.
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4
Merge the files
Click Merge and wait a few seconds while your browser combines the PDFs locally.
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5
Download your merged PDF
Click Download to save the merged file. All originals remain unchanged.
More files today? Free covers 3 tasks a day and files up to 50MB. For unlimited tasks and bigger files, Pro passes start at £1 for 24 hours. One-off payment, no subscription, and your files still stay on your device.
Intent guide
Confidential merges are usually bundles: a contract with its schedules, statements for a lender, or evidence for a claim. Getting the order and the contents right matters as much as privacy.
Why merge locally
Merging is a simple job (the pages are copied into one new file) so there is no technical reason to upload contracts or statements to a server to do it. PDFWhisk reads each file in your browser, copies the pages with pdf-lib and saves the new PDF to your device; the server never receives the documents.
How to check for yourself that nothing is uploaded
On a laptop, open your browser's developer tools (F12, or Cmd+Option+I on a Mac), choose the Network tab, then run the tool. You will see the page's own scripts load and, on the free tier, one small request to /api/pw-quota with an empty body (it counts free tasks per day). No request carries your PDF: compare the request sizes with the size of your file. The processing itself is done by pdf-lib and pdf.js running in the tab.
Build the bundle in a sensible order
Put any index or covering letter first, then the main document, then supporting evidence in date order. Check each file's first-page preview before you merge so an old version or the wrong month's statement does not slip in. If a file has pages that should not be shared, remove them with Delete Pages before merging.
Password-protected files
A PDF that needs a password to open cannot be merged until it is unlocked, and merging does not carry a password over to the new file. If the bundle must be protected, merge first and then use Protect PDF on the result, and send the password by a different channel from the file.
Before you upload/share
- Open the PDF and check every page before you send or upload it.
- Keep the original files until the recipient or portal has accepted the document.
Frequently asked questions
Does this upload my file?
No. Supported PDFWhisk tools process files locally in your browser without uploading the document to a processing server.
Can I use this on a phone?
Yes. PDFWhisk is mobile-friendly, though desktop is usually better for very large files.
Is the output quality preserved?
Yes for merge/split/delete/rotate workflows, because the pages are reorganised rather than aggressively recompressed.
What to do next
Chain tools together for a complete workflow.
Popular searches for this tool
Intent-specific pages for common real-world tasks (upload limits, email attachments, iPhone workflows, and privacy-first processing).