Posted by: Brad. I found an interesting article that proposes a math equation for suggesting the age of people you should be willing to date. I really thought it worked well at the lower age ranges but in the 40s things started to get a little excessive first for the upper limit and then later for the lower limit as well. For example, my dad happens to be 57 years old. The equation given would suggest that his optimal dating range would be between With that in mind, I decided to try my hand at an equation by adding a hard cap to to both the upper and lower limit. The new equation created using excel is:.