Cut each PDF page top/bottom or left/right so one page becomes two or four — ideal for two-up book scans and A3 impositions. Choose a page range, set how many cuts, optionally keep the original page. All processed locally, nothing uploaded.
Merge several PDFs into one with no size limit and no watermark. Drag to reorder, and choose which pages to take from each file (1-3,5 syntax). All local, nothing uploaded.
The PDFs you deal with day to day tend to hold exactly the material that should not leave the building: contracts, expense receipts, bank statements, medical results, proposals that are not final yet, scanned ID documents. The mainstream online PDF services all require an upload first and a download afterwards, and the part in between is something you cannot verify. The two tools here read and write your files locally through a PDF library running in the browser; once the page has loaded you can work offline, and the file never triggers a single network request.
Merging is mostly about turning scattered material into one submittable document: a handful of digital invoices, a report exported chapter by chapter, a contract scanned into several files. Beyond joining files end to end, you can also pick which pages to take from each one — for example 1-3,5 keeps pages 1 to 3 and page 5, so there is no need to delete the unwanted pages first. Splitting solves a different problem: a book scan that captured two pages at once, or an A3 imposition sheet from the printer, has to be cut along the gutter into single pages before it will page properly on a phone or an e-reader.
There is no cap on file size or page count; the real ceiling is your device's memory. A few dozen megabytes and a few hundred pages usually finish in seconds on a modern computer. A scan running to hundreds of megabytes may take the browser considerably longer, and the page shows progress rather than appearing to hang. On a phone, very large files risk being reclaimed by the system — in that case switch to a computer rather than to an upload-based tool.
The usual business model for a free PDF service is two conversions a day, a watermark on the export, or "no watermark" sold as a paid feature. This site has no accounts, so there is no quota to meter and no paid tier to advertise — which leaves no reason to stamp anything on your file. Bookmarking the page is the entire cost of using it.