What's your biological age? Experts explain the benefits and risks of at-home tests

AgingWhat's your biological age? Experts explain the benefits and risks of at-home testsIt’s important to understand what over-the-counter biological age test kits can — and can’t — do before buying them.Listen to this article with a free account00:0000:00Your chronological age may not match your biological age.Chelsea Stahl / NBC News; Getty ImagesShareAdd NBC News to GoogleApril 5, 2026, 8:00 AM EDTBy Lindsey LeakeYou may think you know how old you are, but your body doesn’t follow a calendar.Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.That is, your chronological age, which measures how many years have passed since you were born, may not match your biological age, which reflects wear and tear on your body at a cellular level.Based on factors including genetics, lifestyle habits and medical history, you may be biologically older or younger than your chronological age. That’s because these two measures don’t always progress at the same pace, according to Dr. Douglas Vaughan, director of the Potocsnak Longevity Institute at Northwestern University’s Feinberg School of Medicine.“Every time you have a birthday, you add another year to your life,” Vaughan said. “We all experience that at the same rate, and it’s relentless, it’s unforgiving, it’s cosmically indifferent.”On the other hand, biological age, also called epigenetic age, “reflects more of the changes inside you that occur over time,” he said.Scientists have developed a number of ways to estimate biological age, including so-called epigenetic clocks that measure changes to DNA at the molecular level. These clocks, often created for clinical research purposes, are becoming mainstream in the form of direct-to-consumer test kits.“We have lots of tools now that allow us to get some insight into a given individual’s biological age,” Vaughan said. “This whole field is exploding right now, as we learn that there are ways to measure biological age that we nev...