Britons can now get a personalized life expectancy estimate using a new calculator from the Office for National Statistics (ONS).. The tool, launched this week, forecasts average lifespan based on current age and gender, along with the odds of reaching key milestones like 68, 90, and 100 years old. The ONS also projects that by 2049, one in four girls and one in five boys born in the UK will live to at least 100.

The 2049 centenarian boom

According to the ONS, the calculator reflects broader trends in longevity. The agency estimates that 26% of girls and 21% of boys born in 2049 will reach their 100th birthday—a significant increase from previous generations. This shift is driven by advances in healthcare, improved living conditions, and better disease prevention, according to the report.

How the calculator works

The ONS tool is simple to use: input your age and select your gender, and it generates an average life expectancy. It also provides probabilities for recahing specific ages, such as 68 , 90, and 100. For example, a 30-year-old woman today has a 50% chance of living to 90, according to the calculator. the ONS notes that these estimates are based on current mortality trends and do not account for future medical breakthroughs or unforeseen events.

Limitations and unknowns

While the calculator offers personalized insights, it has limitations. The ONS acknowledges that life expectancy can be influenced by factors beyond age and gender,such as socioeconomic status, lifestyle choices, and access to healthcare. Additionally, the tool does not predict individual outcomes—only averages based on population data. As the ONS report states, "These figures are estimates and should be interpreted with caution."