QR Code help



Hi ALL bar codes i put on my page can be made bigger I have been playing with the QR COdes is there a way to make the image bigger when you place it on a page no matter how much you drag your box out the qr seems to be fixed in size I have 4 Qr Readers some worth 100s of Dollars and none can read at the size it goes on the page i have to zoom in 200% on the document to make it readable.  Any help wouls be great