The size of Mirboo is approximately 75.9 square kilometres. It has 36 parks covering nearly 0.2% of total area. The population of Mirboo in 2011 was 562 people. By 2016 the population was 290 showing a population decline of 48.4% in the area during that time. The predominant age group in Mirboo is 50-59 years. Households in Mirboo are primarily childless couples and are likely to be repaying $1000 - $1399 per month on mortgage repayments. In general, people in Mirboo work in a managers occupation. In 2011, 83% of the homes in Mirboo were owner-occupied compared with 82.1% in 2016.