Nicaragua is 6.2 times larger than El Salvador.
Area: 130,370 km2 World Factbook
Population: 5,848,641 (July 2014) World Factbook
Nicaragua, officially the Republic of Nicaragua, is the largest country in the Central American isthmus, bordering Honduras to the north and Costa Rica to the south. Wikipedia
Area: 21,041 km2 World Factbook
Population: 6,125,512 (July 2014) World Factbook
El Salvador, officially the Republic of El Salvador, is the smallest and the most densely populated country in Central America. The country's capital city and largest city is San Salvador. Important cultural and commercial centers for Central America on the whole include Santa Ana and San Miguel. Wikipedia