There really is no standard width.
Runway dimensions are based on the critical aircraft (the largest aircraft that will regularly use the airport) This aircraft is used for the design of the airports and does not limit larger aircraft from operating there.
Most international airports have a runway 60m wide. Length is based on physical constraints and/or length required for the critical aircraft.
Typical runway lengths can vary from 6,000' to over 11,000. Smaller airports are usually 5,000' or less.