Cost of living in Bridgeport, Connecticut (United States) is 58% more expensive than in Zaragoza (Spain)
This comparison is lacking data. It provides a decent comparison, but it is not yet reliable. It is based on 279 prices entered by 36 different people.
For example, you would need at least €4,270 ($4,991) in Bridgeport, Connecticut to maintain the same standard of living that you can have with €2,700 in Zaragoza.