📎 Unisci PDF

When to use a PDF merging tool

This tool combines multiple PDF files into one, letting you drag and reorder documents before merging, all processed locally in your browser.

When to use it

• You need to send multiple PDF documents (invoices, contracts, attachments) as a single file instead of separate attachments.
• You want to assemble a single dossier from several scans or documents generated separately.

When NOT to use it

• You also need to edit the page content while merging (adding text, signatures): in that case you need a full PDF editor, not just a merging tool.

Alternatives

• A full PDF editor (our editor-pdf) when you also need to edit or annotate pages beyond merging them.
• Command-line tools (e.g. pdftk, qpdf) for automated PDF merging at large volumes.

Common mistakes

• Uploading files in the wrong order: always check the document order before generating the final PDF, dragging them to reorder if needed.
• Merging password-protected PDFs without first removing the protection, an operation the tool can't do automatically.
• Not checking the resulting file's total size when merging many PDFs with heavy images: consider compressing it afterward with our PDF compressor.