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Merge Large PDF Files

Merge large PDF files up to 50MB each — albums, design drafts, and long reports combined in seconds locally. No upload or download waiting, saving time and data, all in your browser.

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Key features

Up to 50MB each

Support a single 50MB PDF, so albums and design drafts merge with ease.

Seconds locally

Processed in your browser. A file of dozens of MB usually finishes in seconds with no upload waiting.

Saves data

No server upload. Download right after merging — large files skip the network round trip.

Lossless stitching

Large files are merged without compression. Images, vectors, and text stay sharp as the originals.

How to use

  1. Upload large PDFs

    Drop multiple large .pdf files (up to 50MB each).

  2. Arrange the order

    Drag thumbnails to set the merge order.

  3. Merge and download

    Merge locally and download the large PDF directly.

FAQ

How large a PDF can I merge?

Each source file can be up to 50MB, and you can merge many; the total is limited by browser memory. A report of dozens of MB usually finishes in seconds.

Will large files lag while merging?

Local browser processing skips the network waiting of upload and download, so merging is usually smooth. For extremely large files, merge in batches.

Do large files get uploaded to a server?

No. Everything runs locally in your browser. Large files never leave your device, which also saves data.

Will images blur after merging?

No. PDF merging is lossless stitching, so images and vectors in albums and design drafts keep the clarity of the originals.

What if large files merge slowly?

Speed depends on page count and browser performance. Close other heavy tabs, or split and merge in batches.