How to Make a QR Code for a PDF, Menu, or Downloadable File
A QR code can't literally contain a PDF — QR codes hold a limited amount of data (a few thousand characters at most, and realistically much less for a code that still scans reliably at a normal print size), while even a short menu PDF is many times larger than that. What a "QR code for a PDF" actually does is encode a URL pointing to where that file already lives online — the scan opens a link, and the phone downloads or displays the PDF from there, the same as clicking a download link in a browser.
Where to actually host the file
The QR code itself doesn't care where the PDF lives, but where you host it determines whether the code keeps working. A few realistic options, roughly in order of what most small businesses already have available:
Your own website, if you have one — uploading the PDF to your site and linking directly to that file's URL is the most durable option, since it's under your own control and doesn't depend on a third-party service's free-tier limits or account status.
Google Drive or Dropbox, using the file's "share" link set to "anyone with the link can view." This is the fastest option if you don't have a website, but it comes with a real caveat: if the file gets moved, renamed, or the sharing permission gets accidentally changed later, the link breaks silently — the QR code still scans fine, it just leads to an error page. Worth checking periodically if this is your only hosting option.
A dedicated menu or file-hosting service, common in the restaurant industry specifically — these exist precisely to solve the "where do I put a PDF menu" problem, though they add a recurring cost most of the free options above don't.
Building the code
Once the file is uploaded somewhere and you have its direct link, paste that URL into the generator exactly as given — the code itself is a completely standard static URL code at that point, no different in kind from a code linking to any other webpage.
Menus specifically: consider a page instead of a raw PDF
For restaurant and shop menus specifically, linking straight to a PDF file has a real downside compared to linking to a normal webpage: a PDF often doesn't resize well for a phone screen (forcing pinch-zooming to read it), doesn't update without re-uploading and hoping the link didn't change, and can't easily show which items are currently out of stock. The fuller restaurant and small-shop menu setup guide covers the tradeoffs between a PDF menu and a proper mobile-friendly menu page in more depth — a PDF is the fastest thing to set up today, a page is usually better once you're past the "get something live this week" stage.
A durability note
Because the QR code itself is static, it will keep encoding the same link forever — the risk to a PDF-linked code isn't the code, it's the file's hosting location changing or disappearing. If you ever move the PDF, updating it at the exact same URL (rather than a new one) is the only way to keep an already-printed code working without reprinting it.
The short version
A QR code for a PDF is just a normal link code pointed at wherever the file is hosted — the real decision is where to host it (your own site is most durable, cloud storage is fastest to set up) and whether a static PDF or a proper mobile page actually serves your readers better, especially for something like a menu that changes over time.