PDF Tools

About these pdf tools

PDF is a container format, not a document format in the way a Word file is. A PDF holds page objects, embedded fonts and images, and a set of instructions for drawing them. That structure is why most edits to a PDF are cheap and lossless: moving, copying, deleting or rotating a page rearranges references to existing objects without re-encoding any content.

The tools here split into two groups. The lossless group - merge, split, rotate, organise, watermark, page numbers - works directly on the page tree with PDF-LIB where existing page content is preserved without unnecessary rasterization for operations that do not require re-encoding. The re-encoding group is smaller: compress PDF rasterises image content at a chosen quality, and PDF to Image renders pages to bitmaps. Both deliberately trade some quality for a smaller or differently-shaped result.

This matters when you are handling documents that have to remain legally or professionally intact. Rotating a scan back to upright, or stamping a contract as a draft, does not alter the underlying text or the embedded images at all. Compression does alter them, which is why it is the one tool in this category that warns you about quality before you run it.

Every one of these tools operates on your own device. That is not incidental for this category: the documents people most often want to merge, split or redact are contracts, invoices, medical letters and identity documents, which are exactly the files that should not be passing through an unknown server.