Calabro was born in The Hague, the son of a Sicilian father and a Dutch mother, and started his footballing career with the youth team of Feyenoord. Failing to break through to the first team, he began his senior career with hometown club ADO Den Haag, making his debut in a play-off match against Sparta Rotterdam in May 2002. After playing for ADO for two seasons, he was signed by FC Utrecht.
In his first season for Utrecht, Calabro featured regularly for the first team, but after falling out of favour in his second season, he moved to FC Volendam, before signing for Helmond Sport a season later. In May 2007, it was announced that he would sign for VVV-Venlo. In the 2008/2009 season, he was crowned topscorer of the Jupiler League, as VVV-Venlo were promoted to the Eredivisie.
On 18 May 2010, Calabro moved on a free transfer to Swiss team FC St. Gallen, signing a contract until 30 June 2012.