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Put a QR code on your business card or email signature so people can save your contact details with one scan.
No. The content is stored in the code itself (a static QR code), so it works forever and doesn't depend on any server.
Yes. It's completely free with no signup, no watermark and no file limits. Everything runs in your browser — files are never uploaded, there is no signup and no watermark.
Yes. Upload a logo and ofyz raises the error-correction level automatically so the code still scans.