You could simply stick to your chronological age.
You could take one of those online tests reviewing lifestyle habits and genetic influences that may add or subtract years from your chronological age.
Or you could simply ask yourself "What age do I feel inside?"
You may surprise yourself.
It was certainly a surprise when my husband Bob asked this of my 90-year-old grandmother nearly 40 years ago.
She had been sitting quietly as my mother and Aunt Ruth discussed her and her medical challenges as if she weren't present. Feeling bad for her, Bob struck up a conversation by asking her what age she felt inside.
Her eyes twinkled. "Oh, eighteen, of course," she said with a smile. "I've always felt eighteen inside!" And she began to flirt with him, showing a glimpse of the lovely young woman living within.
I told this story to my friend Mary and her husband John recently as we sat on their patio overlooking the golf course in an active adult community near Los Angeles. John, who is 80, had been talking about how frustrated he was by the limitations imposed on him by age -- and others' assumptions about older people. "I have so many ideas..." he said, trailing off.
He said that when he considered his inside age, it would have to be about 50 -- a time when he was at the top of his game as an executive with an international corporation. The executive within continues to come up with ideas and insights, frustrated by the physical limitations and advancing age that lead others to assume that he's content to sit in the sunshine, watching others play golf.
Mary smiled and said that she feels like the fun-loving girl she was at 17, sneaking out at night to join her friends, spending sunny days on the beach in Malibu. Chronologically, those days are more than half a century behind her, but something of the lively teenager she once was lingers in her warm engagement with life, with her laughter and her enduring love for her friends. She has been super responsible and conscientious for years now, but there is a part of her still celebrating in the sun.
She asked me how old I felt inside. I thought for a long time. "Maybe 32 or 33, " I said at last. "I feel young, but mature. I first felt that way in my early thirties. That was a time of new professional and personal beginnings, a time of reinventing myself which I seem to keep doing again and again. I still feel the energy and ambition I felt then."
That's the short and easy answer. But there are times when I feel like my shy eight-year-old self or my self-conscious adolescent self, amazed that I can handle a stressful situation without anyone discovering how uncertain I really am. And there are times when I'm tired or discouraged and feel suddenly, temporarily, quite old.
I saw the Tony-award winning Broadway musical "Fun Home" in June when I was in New York and was intrigued by the fact that, in this musical adaptation of cartoonist Alison Bechdel's memoir, three actresses portraying her as a child, as a college student and as a mature adult were onstage together much of the time, sometimes playing separate scenes, sometimes harmonizing. And it occurred to me that we are all comprised of the various versions of ourselves at different ages -- sometimes in discord, sometimes in harmony. And there are times when the self at a certain age prevails.
How old are you inside?