It is not the width. It is measured diagonally through the pan, i.e. from the upper left part of the handle to the lower right part of the handle. Here are all the details:
Base diameter: 22.5 cm
Width: 21 cm
Diameter: 27 cm
Weight: 4,5 kg
Heat resistance: yes
Height without lid: 9.7 cm
Height: 14.5 cm
Induction capability: yes
Length: 33.5 cm
Volume: 3.2 l