How the French passport photo process works
France requires a 35×45 mm photo with the head measuring 32–36 mm from chin to crown, filling 70–80% of the frame, taken within the last six months. The defining French rule is the background: it must be plain light grey or blue-grey — pure white is explicitly not accepted, which catches out applicants used to other countries. The same photo is used for the passport and the carte nationale d'identité. Many French photo booths (photomatons) and approved photographers print a sheet that already carries the compliance markings the préfecture looks for. Snapfora sizes to 35×45 mm, lets you set a light-grey background, and shows the 32–36 mm head band so your photo meets the French spec rather than a generic white-background one.