Though the exact number is disputed, as many as 512 violins made by Antonio Stradivari are known to exist as of 2015. However, not all are in playable condition. It's estimated that the violin maker completed no more than 1,100 instruments in his lifetime, including violins, cellos, violas and guitars.
A genuine, authenticated Stradivarius violin might bring as much as several million dollars at auction, but most violins bearing the Stradivarius label are not genuine, and the chances of finding an unknown and authentic Stradivarius are scarce. Stradivari was one of several famous violin makers operating in Cremona, Italy during the late 17th and early 18th centuries. Others were Amati and Guarneri. All three produced violins that are considered some of the best ever made.