如何在线合并 PDF 文件 — 免费指南

Merging PDFs is useful when you need to submit multiple documents as a single file — such as a cover letter with a CV, a contract with its appendices, or multiple scanned pages from a flatbed scanner.

Merging also simplifies file management: instead of tracking dozens of separate files, you keep one combined document that's easier to email, share, and archive.

1. Go to the WhiskFile Merge PDF tool.

2. Click "Choose files" or drag and drop your PDFs onto the upload zone. You can add up to 20 files at once on the free plan.

3. Arrange the files in the order you want them to appear in the final document. Drag each file card to reposition it.

4. Click "Merge PDF". Processing takes a few seconds per file.

5. Download the merged PDF. The output file will contain all pages from all input files in the order you specified.

Yes. WhiskFile automatically converts JPG, PNG, and TIFF images to PDF before merging, so you can mix document formats in a single merge operation. Upload your PDFs and images together and they will be combined in the order you arrange them.

Hyperlinks within the individual PDFs are preserved in the merged output. Bookmarks (table of contents entries) from the original files are also preserved.

Cross-document links (links from one input file that point to a page in another input file) will not automatically update to the new combined page numbers. If cross-document links are important, use the WhiskFile Create PDF Bookmarks tool after merging to rebuild the navigation structure.

Make sure all files have the same page size (A4 or Letter) before merging, or the result may have inconsistent page dimensions. Use the WhiskFile Resize PDF tool to standardize page sizes first.

If file size is a concern after merging, run the result through the Compress PDF tool. Merging itself does not increase file size beyond the sum of the inputs, but compressing the output can reduce it further.