The size of Koolunga is approximately 207.2 square kilometres. It has 4 parks covering nearly 0.5% of total area. The population of Koolunga in 2011 was 379 people. By 2016 the population was 204 showing a population decline of 46.2% in the area during that time. The predominant age group in Koolunga is 50-59 years. Households in Koolunga are primarily couples with children and are likely to be repaying $800 - $999 per month on mortgage repayments. In general, people in Koolunga work in a managers occupation. In 2011, 83.4% of the homes in Koolunga were owner-occupied compared with 75.3% in 2016. Currently the median sales price of houses in the area is $92,000.