Tonga is 37% larger than Guam.
Area: 544 km2 World Factbook
Population: 161,001 (July 2014) World Factbook
Guam is an organized, unincorporated territory of the United States in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Wikipedia
Area: 747 km2 World Factbook
Population: 106,440 (July 2014) World Factbook
Tonga, officially the Kingdom of Tonga, is a Polynesian sovereign state and archipelago comprising 176 islands with a surface area of about 750 square kilometres scattered over 700,000 square kilometres of the southern Pacific Ocean, of which 52 are inhabited by its 103,000 people. Wikipedia