The size of Forthside is approximately 13.8 square kilometres. It has 8 parks covering nearly 42.9% of total area. The population of Forthside in 2011 was 1,024 people. By 2016 the population was 67 showing a population decline of 93.5% in the area during that time. The predominant age group in Forthside is 0-9 years. Households in Forthside are primarily couples with children and are likely to be repaying $1800 - $2399 per month on mortgage repayments. In general, people in Forthside work in a managers occupation. In 2011, 83.3% of the homes in Forthside were owner-occupied compared with 71.4% in 2016.