Under AVPN rules, a true Neapolitan pizza may have a maximum diameter of 35 cm.
The Associazione Verace Pizza Napoletana, or AVPN, uses a maximum diameter of 35 centimetres in its specifications for verace pizza napoletana. The measurement applies to the finished round pizza, whose characteristic raised rim, or cornicione, surrounds a soft and thin centre.
Diameter is only one part of the standard. AVPN rules also address the ingredients, dough handling, shaping and baking. The dough is made from flour, water, salt and yeast, formed by hand rather than rolled with a pin, and traditionally baked at very high heat for roughly 60–90 seconds. Classic recognized varieties include marinara and Margherita.
The 35 cm limit should not be mistaken for a universal size rule for every pizza sold in Naples. Many excellent pizzas fall outside formal certification systems. It is specifically the maximum associated with the AVPN definition of true Neapolitan pizza, which is why 55 cm, 45 cm and 25 cm are not correct choices.