Merge PDF
Combine two or more PDF files in any order you choose. Reorder files via drag and drop, verify page counts, and download a consolidated PDF in seconds.
Merge PDF
Combine two or more PDF files in any order you choose. Reorder files via drag and drop, verify page counts, and download a consolidated PDF in seconds.
How to Use Merge PDF
- Step 1: Upload multiple PDF files
- Step 2: Arrange files in your preferred sequence
- Step 3: Click Merge PDF and download the result
Technical Specifications & Limitations
- Maximum file size: Up to 100 MB per individual PDF document.
- Maximum batch size: Combines up to 50 PDF files simultaneously.
- Encrypted files: Password-protected PDFs must be unlocked before merging.
- Form fields: Interactive AcroForms are flattened into vector content to prevent field name collisions.
Troubleshooting Common Issues
⚠One of my files failed to upload or display a page count.
The PDF may be encrypted with a permissions password or corrupt. Use the 'Unlock PDF' tool first to remove security restrictions, or re-save the PDF from your viewer.
⚠The merged PDF order is incorrect.
Drag and drop the file cards in the upload area to re-sequence them before clicking 'Merge PDF'.
⚠Browser freezes on large PDF collections.
Merging very large files (over 200 total pages) requires substantial browser RAM. Process files in batches of 10 to 15 for optimal responsiveness.
🔒Privacy & Security Guarantee
All PDF processing for Merge PDF occurs 100% inside your local web browser sandbox using WebAssembly and client-side JavaScript. Your documents, images, and data are never transmitted over the internet or saved to external servers. Full confidentiality is preserved for sensitive scientific research, financial records, and legal contracts.
Frequently Asked Questions
Are my merged documents uploaded to any server?
No. All PDF merging is executed entirely in your local browser sandbox using WebAssembly and JavaScript. No files or metadata are transmitted across the internet.
Does merging reduce text quality or vector sharpness?
No. SciHive merges the underlying PDF object trees losslessly. All vector curves, typography, and embedded images maintain their original fidelity.
Can I add page numbers to the newly combined document?
Yes. Once you download your merged PDF, you can run it through our 'Add Page Numbers' tool to create continuous pagination across all combined chapters.
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