Merge PDF files on your computer, not in someone else’s queue

School admissions, visa packets, and small-business onboarding still want “one PDF.” You already have five: a scan, an email attachment, a downloaded form, a photo-as-PDF, and a letterhead export. The usual fix is a website that accepts uploads, stitches the files, and emails a link. That is a reasonable engineering shortcut. It is a poor fit when the packet includes IDs, medical letters, or a bank statement.

Merge PDF on Tool Hub merges PDFs in the tab. The files stay on your computer. We do not take a copy to stitch on a server.

When merge is the right tool

Merge is for files that are already PDFs, in the order you want. It is not OCR. It will not magically make a photograph of a whiteboard into searchable text. It is not redaction. Cutting a page out of a scan is not the same as blacking a number on a page you still send — if a number must disappear, do that in a tool you already trust, or wait for our redaction product to go live. Do not upload the packet to a random “redact online” site in the meantime.

Split is the sibling job: one fat scan that should be three attachments. Use Split PDF locally. Do not upload an 80-page pack to extract pages 12–14.

How to merge on Tool Hub

1. Open https://tools.sw-commercial.com/merge-pdf.
2. Open the PDF merge tool.
3. Add the files in the order the recipient asked for. Rename them on disk first if that helps you sort (01-cover.pdf, 02-id.pdf).
4. Confirm the page count looks right in the preview.
5. Download the combined PDF. Open it in a second reader and scroll once before you send it.

There is no account. Free merge does not stamp a watermark that you then have to pay to remove.

Ordering mistakes that waste a day

Recipients are literal. If the checklist says “passport, then bank letter, then proof of address,” that is the merge order. A cover sheet you forgot is easier to add as another PDF than to explain in email.

Phone scans often land as one image per page in a huge file. Merge will keep that bulk. If the packet bounces on an email size limit, compress on the hub after you are sure the content is right — compress is not a substitute for deleting the wrong appendix.

Do not merge the original of a document you already redacted with the redacted copy “just in case.” You will undo the redaction by attaching the source.

What the browser is doing

The hub loads pdf-lib (and related code) into the page. Your browser reads each file you picked and writes a new PDF. That is why a 200-page merge can make a laptop fan spin and why a phone may prefer two smaller merges. It is also why airplane mode still works after the page has loaded: there is no job id on our side.

Ads, Pro, and the file path

Some hub pages may show labeled ads. Ads do not receive the PDFs. SW Toolbox on the Chrome Web Store can run related jobs from the browser chrome, with 0 ads in the extension. Pro is optional and one-time. Merge of ordinary packets does not require it.

If you want the same merge from Cursor or Claude, use the local MCP hub at tools.sw-commercial.com/mcp. It listens on your machine at 127.0.0.1:17321. It is not a way for us to collect the packet.

After you send it

Keep the merged file and the inputs until the recipient confirms. If they ask for a missing page, merge again from the inputs rather than editing a file you already emailed — version confusion is how the unredacted scan gets back into circulation.

Image-only scans mixed with real PDFs

A phone scan is often a JPEG wrapped in a PDF. A Word export is text. Merge keeps both. The combined file can be large and not searchable on the photo pages. That is expected. If the recipient needs to search, run OCR in a tool you already trust on your computer, then merge — do not upload the packet to a random “OCR online” site. On-device OCR from this family is launching soon.

Rotate pages before merge if a scan landed sideways. Merging first and rotating later is extra work in some readers and easy to forget on page 19 of 20.

Email and portal size limits

Many school and government portals cap uploads at 5 or 10 MB. Merge, then check the file size on disk. If it is over the cap, compress on Tool Hub or split into the parts the portal allows. Do not screenshot every page into a new Word file; that is how people create a third, worse copy of an ID.

The tool is live at tools.sw-commercial.com/merge-pdf. This page is the how-to for that URL, not a placeholder for a future product.