Combine two or more PDFs into a single document — free, no sign-up, and completely private.
Most "free" PDF mergers upload your documents to a server, process them there, and often add a watermark or a paywall once the file gets large. meldpdf does the whole job on your own device. That means contracts, invoices, bank statements and other sensitive documents never travel across the internet — which is both faster and far more private.
No fixed limit. Because processing happens on your device, very large jobs depend on your computer's memory rather than a server quota.
No. Pages are copied exactly, so text stays selectable and images keep their original resolution.
No. We have no server that receives your files — everything stays in your browser. See our privacy policy.
Each PDF you add may contain internal bookmarks (a clickable table of contents), hyperlinks, and cross-references. When files are merged, bookmarks that pointed to a page within the same source file continue to work because the page is still present in the combined document. However, bookmarks that referenced a page by a named destination in a different file will not resolve automatically — the merge tool preserves page content, not inter-file link targets. If your final document needs a working table of contents that spans all the source files, the simplest approach is to create one after merging using a PDF editor that supports bookmark editing.
External hyperlinks — URLs that open a website — are unaffected by merging. They are stored as annotations on each page and carry over exactly as they were.
Desktop PDF editors like Adobe Acrobat or PDF-XChange offer merging as one feature among many, but they require installation, often a paid licence, and updates. Online services handle it on a server, which is convenient but means your files travel over the internet and sit on someone else's machine, however briefly. A browser-based tool like meldpdf splits the difference: there is nothing to install, the merge runs instantly using the JavaScript engine built into your browser, and your documents never leave your device. The trade-off is that extremely large files (hundreds of megabytes) may be slower than a native desktop app, because browsers allocate less memory than a dedicated program. For everyday merges — combining a handful of documents under 50 MB total — the browser approach is the fastest and most private option available.
Not directly. A PDF that requires a password to open is encrypted, and the merge library cannot read its pages without decrypting it first. Open the file in any PDF reader, enter the password, and export or print it to a new unprotected PDF. Then merge that copy. If the PDF only has a permissions password (restricting printing or editing but not opening), most merge tools — including this one — can process it normally.
There is no hard limit set by the tool. The practical ceiling depends on your device's available memory. Most laptops and desktops can comfortably handle a combined total of 100-200 MB. If you hit a memory wall, try closing other browser tabs first, or merge in batches: combine the first half of your files, then merge that result with the second half.
Last updated: 3 September 2026.