05 / PAN SIZE GUIDE
Pan size guide
A recipe calls for a 9-inch round pan and you're holding two pans that both look about right. This shows common pan sizes at their true physical size on your screen, so you can hold the actual pan up to it and compare directly, instead of guessing.
Screens report pixels, not inches, so without calibration this is a rough guess. Calibrate once and it's accurate on this device from then on.
Round cake pans, true size
Ruler
Why this needs calibration
A "pixel" isn't a fixed physical size. A 15-inch laptop and a 27-inch monitor can both report the same pixel width for an element while being completely different sizes in the real world, since they pack different numbers of pixels into an inch of actual screen. Without knowing your screen's real pixel density, any "actual size" comparison is a guess dressed up as a fact.
The card method is the most reliable: nearly everyone has a credit card, debit card, or ID card nearby, and they're all manufactured to the same standard size worldwide (85.60 × 53.98 mm). Matching that on screen gives a real, physical reference point, no guessing about your device model required.