PDFファイルを1つの文書に結合する方法

Merging PDF files is one of the most common document operations. Combining several files into one is useful when you have separate scans, invoices, reports or contracts and want to create a cohesive document. OptimaPDF offers a free PDF merging tool that works entirely in your browser.

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Merge PDF

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How to Merge PDF Step by Step

Add PDF Files

Drag and drop PDF files into the upload area or click to select them from your disk. You can add multiple files at once — we support any number of files.

Arrange File Order

You can drag files to change their order. The top file will be first in the merged document. Tip: add the file that should come first first.

Click "Merge PDF"

The merging process usually takes a few seconds. Once complete, the file will be downloaded automatically. The merged document retains the pages, formatting and quality of the original files.

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Merge PDF

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When is PDF Merging Useful?

Combining several scanned pages into one document
Merging invoices and reports into one file for accounting
Creating a single file from multiple contracts or legal documents

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Merge PDF

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Frequently Asked Questions

How many files can I merge at once?

There is no limit on the number of files — you can add as many PDFs as you need. The only limitation is your browser's memory. In practice, the tool handles a dozen files without any issues.

Does merging PDFs affect document quality?

No, merging does not change file contents. Each page remains in original quality and text and images are not modified. The tool combines files into one document without re-encoding pages.