Western Australia (Australia) is 4.9 times larger than Thailand.
Area: 513,120 km2 World Factbook
Population: 67,741,401 (July 2014) World Factbook
Thailand, officially the Kingdom of Thailand, formerly known as Siam, is a country at the centre of the Indochina peninsula in Southeast Asia. Wikipedia
Western Australia is a state occupying the entire western third of Australia. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Southern Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east. Wikipedia