How many stone water jars did Jesus have filled at the wedding in Cana?

Answer: Six

Six stone jars used for Jewish purification rites were filled to the brim with water, which became wine.

“Now six stone water jars had been set there for the Jewish rites of purification. Each could hold from twenty to thirty gallons. Jesus told the servants, “Fill the jars with water.” So they filled them to the brim.”— John 2:6-7 (BSB)