A free QR code generator should mean you can make the image and leave. This page does that. It is the same tool as the QR code generator, described around the two limits people run into elsewhere: a code that dies when a trial ends, and a download locked behind an account. Here the pattern is built in the browser from the text you type. Download PNG for a screen, or SVG if you will print. There is no watermark in the squares and no login.
No expiration is a property of what was encoded. The file holds your URL or your sentence. It does not hold a FreeToolCrate address that forwards to you. A camera that scans it never contacts this site. That also means there is no dashboard where you can rewrite the destination next month. When the address changes, generate a new image and put that image where the old one was. If you wanted scan counts, you want a tracking link, and a tracking link is a service that can be turned off. This page is the other kind.
Error correction defaults to M. Move to Q or H for a small print or a surface that gets scuffed. Higher correction is more squares for the same text. The box stops at 900 characters. Shorten a long note rather than expecting a poster-sized code to stay reliable on a phone screen. Leave the blank margin around the pattern. Test with a phone before you publish.
The text is not uploaded. Do not put a secret in the code if the picture will be in public, because every scan reveals it. Styled letters from the fancy text generator will be encoded literally and will break a normal web address. Use the plain URL. When the image looks right and a phone reads it back as the same text, you are done. The file is then yours to keep.