Ruby is a hamlet (and census-designated place)[3] in Ulster County, New York, United States.

The community is 6.3 miles (10.1 km) north of Kingston in the town of Ulster.

Ruby has a post office with ZIP code 12475, which opened on June 2, 1896.

[1] One-time major league baseball player Dutch Schirick was born in Ruby on June 15, 1890.

[6] The Roman Catholic Church of St. Wendelinus was founded as a mission station of St. Peter's in Rondoubt.