Merge PDF

What is PDF merging?

PDF merging combines multiple PDF files into a single document. This is useful for assembling reports from separate sections, combining scanned pages, merging signed documents, or creating a single file from multiple sources for easier sharing and printing. This tool processes everything in your browser — no upload to any server.

The merged document preserves each source PDF's content exactly — text, images, formatting, bookmarks, and page layout are all maintained. You can reorder the files before merging by dragging and dropping them into the desired sequence.

Common use cases for PDF merging

PDF merging is one of the most frequent document tasks across both personal and professional contexts. Here are the most common situations where combining PDFs saves time:

• Combining invoices and receipts — gather monthly expenses into one file for accounting or expense reports.
• Assembling application documents — job applications, rental applications, and visa submissions often require multiple documents in one PDF.
• Joining scanned pages — when a scanner saves each page as a separate PDF, merge them into a single continuous document.
• Merging contract appendices — combine a main agreement with its exhibits, schedules, or signature pages.
• Consolidating reports — pull together weekly or monthly reports from different team members into one shareable PDF.
• E-book or handout compilation — combine lecture slides, reading excerpts, and supplementary material for distribution.

How to use this tool

Upload two or more PDF files by dragging and dropping them or clicking the file picker. Reorder the files by dragging them into the desired sequence. Click merge to combine them into a single PDF. Download the result. The tool shows the page count for each file and the total page count of the merged document.

What is preserved — and what is not

When PDFs are merged, the content of each source file is placed into the output document in the order you specify. Text, images, vector graphics, and page layout are all preserved exactly as they appear in the original files.

Document-level metadata such as the title, author, and subject fields from the source files may not carry over into the merged document, depending on how the merge is performed. If metadata matters for your workflow, review the merged file in a PDF reader and update the properties if needed.

Form fields (fillable forms) are generally preserved in the pages themselves, but interactivity depends on the PDF library used. If your PDFs contain fillable fields that must remain editable after merging, verify the result before distributing.

Password-protected PDFs cannot be merged without first removing the password. If you add an encrypted file, most tools will report an error. Remove the password protection in a trusted PDF reader before attempting to merge.

Managing file size after merging

The file size of the merged PDF is roughly the sum of the source files. There is usually no significant overhead added during merging itself. However, scanned PDFs can be large because each page is stored as a high-resolution image rather than as text. If the merged file is too large to email or upload, consider these strategies:

• Reduce scan resolution — if you control the scanner, 150 to 200 dpi is typically sufficient for readable text. 300 dpi is high quality; 600 dpi is rarely necessary for documents.
• Compress before merging — run each source PDF through a PDF compressor first, then merge the compressed versions.
• Use PDF/A cautiously — archival format PDFs embed all fonts and resources, which increases size.

Tips for merging PDFs

• Check page orientation — mixing portrait and landscape pages in one document works fine but may look inconsistent.
• Verify page order before merging — rearrange files by dragging them in the file list.
• For large merges, check the total page count to ensure no files were missed.
• If file size is a concern, compress the individual PDFs before merging.

Common mistakes to avoid

• Wrong file order — double-check the sequence before merging. It is easy to accidentally reverse the order of pages when dragging files.
• Including a draft instead of the final version — rename files clearly (e.g., contract_final.pdf) to avoid accidentally adding an outdated draft.
• Forgetting to remove blank separator pages — some scanners insert blank pages between documents. Remove them in a PDF editor before merging.
• Merging scanned images without OCR — if you need to search or copy text from the merged PDF, run OCR on the scanned pages first. A scanned PDF is effectively an image and its text is not selectable.

Privacy guarantee

All PDF processing happens locally in your web browser. Your files are never uploaded to any server. The merged PDF is generated entirely on your device using client-side JavaScript. This ensures complete privacy for sensitive documents like contracts, financial records, and personal files.

Frequently asked questions

Can I merge PDFs with different page sizes?

Yes. Each page in the merged document retains its original dimensions. If one PDF has letter-size pages and another has A4 pages, both sizes will appear in the merged file. Most PDF viewers handle mixed page sizes without any issues.

Are bookmarks and links preserved?

Internal bookmarks and hyperlinks within each source PDF are generally preserved. However, cross-document links (a link in PDF A pointing to a page in PDF B) will not automatically work after merging. The tool preserves the structure of each source document as faithfully as possible.

Is there a limit on how many PDFs or pages I can merge?

This tool runs entirely in your browser, so practical limits depend on the memory available on your device. Very large files or a large number of files may slow down or exceed browser memory. For everyday tasks — merging up to 20 or 30 typical documents — you should not encounter any issues.

My PDFs are confidential. Are they safe to use here?

Yes. All processing happens locally on your device using client-side JavaScript. No data is sent to any server. Your files never leave your browser. This makes the tool safe for confidential documents such as contracts, financial statements, and medical records.