The size of Welby is approximately 1.9 square kilometres. It has 4 parks covering nearly 9.5% of total area. The population of Welby in 2011 was 735 people. By 2016 the population was 727 showing a population decline of 1.1% in the area during that time. The predominant age group in Welby is 0-9 years. Households in Welby are primarily couples with children and are likely to be repaying $1800 - $2399 per month on mortgage repayments. In general, people in Welby work in a trades occupation. In 2011, 62.7% of the homes in Welby were owner-occupied compared with 64.6% in 2016. Currently the median sales price of houses in the area is $792,500.