The Short Version: As life expectancy climbs and health care improves, millions of people can now realistically set themselves the goal of reaching at least 100 years old. The potential for longevity is within our genes, and Living to 100 can help individuals and couples unlock the secrets of old age. The Living to 100 website offers a longevity calculator that uses trusted medical research to tell people how long they can expect to live and what steps they can take to live longer, healthier, and happier.

In 1995, the New England Centenarian Study embarked on a research project to identify the defining traits of people who lived past 100. Whether it was looking at healthy eating habits or genetic markers, the goal was to unlock the secrets of a long life.

Today, the New England Centenarian Study is one of the most comprehensive studies of its kind. Thomas Perls MD, MPH, is its founder and director, and he literally wrote the book on living to a ripe old age. Published in 1999, “Living to 100: Lessons in Living to Your Maximum Potential at Any Age” is an educational resource based on research conducted at Harvard Medical School.

Photo of Dr. Thomas Perls, Founder of Living to 100

Dr. Thomas Perls created the Living to 100 Life Expectancy Calculator as a free online resource for health-conscious people.

While doing research for his book, Thomas realized that most people have the potential to live to 86 or 89 years old, depending on gender, but the vast majority of people were failing to live up to that potential. The average life expectancy in the U.S. was about 75 in the 1990s, and today it’s currently hovering at 79.

What caused that 10-year gap between potential and actual life spans? Unhealthy dietary and lifestyle habits. Thomas saw an opportunity to inform the public and promote healthier living, so he created the Living to 100 Life Expectancy Calculator as a free online resource.

The calculator uses a 40-question quiz to determine how long a person can expect to live if they continue on the same trajectory. It can identify unhealthy habits and offer healthful solutions to anyone wondering what he or she can do to increase their life span.

Couples can use this informative tool to adjust their diets and adopt healthier habits so they can maximize their time together. Anyone planning to lead a life together can benefit from consulting the Living to 100 website for important guidance from medical professionals.

Thomas has dedicated his life to the study of health and longevity. He is a professor of medicine and geriatrics at Boston University School of Medicine, and he also cares for patients as a physician at Boston Medical Center. His research project on centenarians has gone a long way toward answering important questions about why someone lives past 100 years old, and how the average person can follow their good example.

“If you can take advantage of the genes that get us to those advanced ages, you can live beyond your 80s or even your 90s,” Thomas said. “The majority of variation in how old we live is related to our health behaviors.”

How 40 Questions Can Help Predict Your Life Span

The Living to 100 questionnaire is straightforward and takes no more than 10 minutes to complete. You start by providing basic personal information (age, gender, marital status, etc.) and then you answer general questions about your stress levels, eating habits, smoking habits, family medical history, medical information, and other health-related factors.

Every answer has a value that can add to or subtract from a person’s overall life expectancy. Women start with a score of 89, and men start with 86.

Unhealthy habits, like smoking and heavy drinking, can subtract from that total score, while positive genetic factors — like having a family member who lived past 96 — can increase someone’s life expectancy quite a bit. The more honest you are in your answers, the more accurate the calculation will be.

Screenshot of the life expectancy quiz

The Living to 100 quiz prompts individuals to assess how well they take care of themselves.

The Living to 100 questionnaire relies on the most recent medical literature to base its calculations, and it weighs each factor differently. The end result can let people know what they’re doing right and wrong in terms of maintaining good health and setting themselves up for a long and prosperous life.

“It’s a public service site and an educational tool,” Thomas said. “The calculator isn’t supposed to give exact life expectancy — it’s not a crystal ball — but it does give you a rough idea of how your day-to-day behaviors translate to a ballpark average life expectancy.”

The Feedback Section Has Tailored Medical Advice

After you’ve taken the test, you can review your results in more detail in the Feedback Section. This offers a clear breakdown of how you can extend your life span and correct potentially life-shortening behaviors.

For instance, I took the test and found out that I can expect to live to 92 years old (hooray!), but I could live up to four years longer by cutting fast food out of my diet. Now, as much as I love Chicken McNuggets and Bic Macs, it’s hard to justify trading four years for those unhealthy meals.

By giving consumers hard data, the Life Expectancy Calculator can really put things in perspective and bring greater awareness to how small daily actions can lead to serious health consequences. It can also recommend medical screenings, vaccinations, and other preventative measures to prolong life.

Screenshot of my quiz results

The quiz results can offer a customized action plan for getting healthy and living longer.

Taken as a whole, the Living to 100 calculator can provide a good barometer to track one’s progress in leading a healthy lifestyle, and its follow-up advice can make sure people know exactly what to do to improve their results.

The health resources on Living to 100 can offer valuable education and intervention tools for at-risk patients and health-conscious folks. Its focus on preventative health measures can do a world of good for people who want to live to 100 but need to change course to get there.

In addition to health information, Living to 100 also recommends financial planning so that individuals and couples are prepared for the more than likely possibility that they’ll spend over 20 or 30 years in retirement. They need to have enough savings to take care of themselves in their golden years, and the time to start planning for that is now.

Encouraging Families to Lead Health-Conscious Lifestyles

Many individuals, couples, and families have used the Life Expectancy Calculator over the years, and it has brought them insight into how their behavior impacts their life span. Sometimes the results are promising and reinforce good behavior, and other times a person has a lot of room for improvement and finds motivation in the idea of mortality.

“Thanks for providing this interesting site,” wrote I.M. in a testimonial. “It’s good to know how one is getting on. I am going to suggest that my husband does the questionnaire — it might frighten him into giving smoking up!”

Couples who take the quiz together can hold each other accountable for making healthful decisions in the future, and it’s a great way to use teamwork to improve the odds of living a long life. When couples tackle diets together or commit to exercising together, they bond over the shared activity and become more committed to following through with their health goals.

“I found this very enlightening… and encouraging!” — anonymous Living to 100 user

The Life Expectancy Calculator can give couples the inspiration they need to make positive changes and start a dialogue in their family about the importance of eating right, getting exercise, and maintaining good health.

When people are proactive about their health, they reap the benefits later in life and can spend more time doing the things they love with the people they love.

A Living to 100 user with the initials J.Y. said that approaching retirement was much more exciting because of an augmented life span. “It was terrific to have a cheery prognostication of nearly thirty years to enjoy it in,” J.Y. said. “Your test was easy and fun to take and encourages me to continue doing what I do well and to address those areas where I know I could improve. Now, if the results only came with a guarantee…”

Living to 100 Offers a Road Map to Aging Well

Since 1995, the medical community has gained more knowledge and insight into what factors can shorten or lengthen a person’s lifespan, and Living to 100 has refined its results accordingly. This longevity calculator can’t see into the future or offer any guarantees, but it can give individuals and couples the opportunity to assess their daily health habits and understand how their choices can give them more time with the people they love.

The Living to 100 calculator is a fun and informative tool for anyone interested in improving and lengthening their lives, so maybe one day they can sit beside a centenarian partner and look back on a life well lived.

Over the years, Thomas has gotten a lot of offers from drug companies looking to make a buck off people’s private medical information and family history, but Living To 100 remains a free educational resource with no targeted ads to speak of.

“I’m all about healthy aging,” Thomas said. “I care a lot about people, so if I can help them, that’s really important to me.”

Advertiser Disclosure is a free online resource that offers valuable content and comparison services to users. To keep this resource 100% free, we receive compensation from many of the offers listed on the site. Along with key review factors, this compensation may impact how and where products appear on the page (including, for example, the order in which they appear). does not include the entire universe of available offers. Editorial opinions expressed on the site are strictly our own and are not provided, endorsed, or approved by advertisers. Our Editorial Review Policy Our site is committed to publishing independent, accurate content guided by strict editorial guidelines. Before articles and reviews are published on our site, they undergo a thorough review process performed by a team of independent editors and subject-matter experts to ensure the content’s accuracy, timeliness, and impartiality. Our editorial team is separate and independent of our site’s advertisers, and the opinions they express on our site are their own. To read more about our team members and their editorial backgrounds, please visit our site’s About page.