Why this is not another upload farm
HR packets, board decks, and signed offers should not become someone else’s object storage. This page merges and splits in the tab using pdf-lib. The library itself loads from a file host (jsDelivr). Your PDF bytes are not posted to Privy Tools. Watch the compute log: you should see a library fetch, not a file upload.
Worked example: offer + annexure
Select the offer PDF, then the annexure, in that order. Merge. Open the result and confirm page 1 is still the letterhead you meant to lead with. Order is the failure mode here. A “wrong appendix in a signed packet” email is worse than a slow merge.
Worked example: hide pricing from a vendor
A 12-page quote. Vendor needs pages 2–4 (scope) and must not see page 1 (rate card) or pages 10–12 (internal margin). Split 2-4. Do not email the original as a “just ignore the first page” attachment. People do not ignore the first page.
Worked example: phone vs laptop
Three 8 MB scans on a mid-range phone will often freeze the tab. That is a memory ceiling, not a conspiracy. Use a laptop for dense scans. The per-file cap in the script is 50 MB; the practical cap is whatever RAM the browser process still has after the PDF library loaded.
What breaks
Password-protected PDFs. Files that look like PDFs but are actually HTML printouts with a .pdf name. Bookmarks and named destinations: pdf-lib will copy pages; outline trees often do not survive the way Acrobat users expect. Digital signatures on the source file are not a merge-safe object. If a bank sent a signed statement, do not “fix” it here and expect the signature to remain valid.
Page numbers in the UI are 1-based file order, not Bates stamps printed in the footer. If legal numbering starts at 00-0147, count yourself.
Questions
Does my PDF get uploaded to Privy Tools?
No. Bytes stay in this tab. pdf-lib still loads from a file host so the tool can run; that hop is the library, not your file.
How do I control merge order?
Select files in the order you want them, then confirm page 1 of the result before you send it. There is no mind-reading sort by filename.
Do bookmarks survive?
Often not. Treat the output as a new document.
Password-protected PDFs?
Usually fail. Decrypt in a tool you already trust, then merge the unprotected copy if that is lawful.
Will a digital signature remain valid?
No. Merging or splitting a signed PDF breaks the signature. Use the original for anything that must stay signed.
Why did my phone tab die?
Raster-heavy scans plus an in-memory PDF library. Try a laptop, or split first.