The size of Karanja is approximately 0.5 square kilometres. The population of Karanja in 2011 was 356 people. By 2016 the population was 23 showing a population decline of 93.5% in the area during that time. The predominant age group in Karanja is 40-49 years. Households in Karanja are primarily childless couples and are likely to be repaying $300 - $449 per month on mortgage repayments. In general, people in Karanja work in a labourer occupation. In 2006, 33.9% of the homes in Karanja were owner-occupied compared with 71.2% in 2011. Currently the median sales price of houses in the area is $14,750.