A QR code that opens a ready-to-send email
On a poster or a card, the person scans and their mail app opens with your address as recipient, a subject line and a starting message already there.
What happens inside the mail app
The code stores an address in mailto format, optionally followed by a subject and a body written into the address itself. On scan, the phone launches the default mail app with all three fields already filled in, so the person only has to check it over, add anything missing, and hit send.
Without a mail app set up on the phone, the scan either fails or offers to install one. That is rarer these days since most phones ship with a mail app ready to go, but it is still worth testing on a few different phones before a large print run.
Where this format earns its keep
A quote request on a building-site sign or a shop window, with the subject already reading something like Quote request for. A job application on a recruitment poster, the subject naming the role. A quick contact route on a business card or an exhibition stand, so nobody has to type out your address and mistype a letter.
What it gives away, and how to use it well
The email address stored in the code stays readable to anyone who decodes it with a reader app, same as any address printed on a public sign. A dedicated address for public enquiries, kept separate from a personal inbox, keeps things tidy if it ever picks up unwanted messages.
The subject and body are baked into a static code, so if they need to change often a dynamic code pointing to an editable page suits better. On paper, leave a white margin, strong contrast and at least 2cm a side, and test with two phones before a large print run.
Questions about the free generator
Does the email send itself on scan?
No. The phone opens the mail app with the draft filled in, but the person still has to hit send after reading it over.
Can I pre-fill the subject and the message?
Yes, both go into the mailto address along with your chosen subject and body, so nobody has to retype everything by hand.
What if there is no mail app on the phone?
The scan may fail or offer to install one. It is uncommon, but worth testing on a few phones before printing in bulk.
Switch to a dynamic code to change the pre-filled subject or message without reprinting the sign. Make it editable