Selected files are read and rewritten in browser memory. Merge and split modes copy PDF pages, while image-to-PDF embeds the selected raster images on newly sized pages.
Compression intentionally rasterizes each page, which can reduce scan-heavy files but removes searchable text, forms, links, annotations, and vector structure. Keep the original file until the result has been checked.
Questions
PDF Merger FAQ
Does merging reduce PDF quality?
No. Existing PDF pages are copied into a new document rather than rendered as images, so their original content quality is retained.
Can encrypted PDFs be merged?
Password-protected or restricted files may not load. Remove protection with authorized software before combining them.