Before you print
How big should it be?
Rule of thumb: printed width ≥ scanning distance ÷ 10. Pick the surface above and the studio sizes the code for you, then checks the printed module size against what a press can actually hold.
Questions people actually ask
A BIP 21 bitcoin: URI — the standard every wallet understands. Scanning fills in your address, plus the amount and label if you set them, ready for the sender to confirm.
Modern bech32 addresses (starting bc1) and legacy addresses (starting 1 or 3). We check the format as you type so a mistyped address can't end up in print.
Yes — an address only lets people send you bitcoin, never spend it. No funds ever touch UseQR; the code is a payment URI generated entirely in your browser, and there is nothing to expire.
Anyone can look up an address's incoming payments on the public blockchain. For a long-lived printed code that is usually fine for donations; for privacy, wallets recommend a fresh address per payer.
Want the detail? How bitcoin QR codes work — the payload format, what scanners do with it, and where it breaks.