The "half the man's age, plus 7" formula already given isn't bad, but others may have a different opinion.

40 for sure. 30s pushing it.

Somewhere between 31 and 36. I picked 31 because at that age (hers) the 10-year differential creates a substantial difference in life stage and experience. I picked 36 because at that age (his) he literally could be her father. I made a range because some 21-year-old women can be especially mature for their age, so she might actually prefer flirting with an older man. I don't like setting anything too firm, but, yeah, somewhere in there is where it starts feeling uncomfortable.

I don't have any daughters. If I did, I'd probably set the bar lower, but this is me without an emotional involvement in the question.

Total Honesty? From this front, here we go. I am 68 years old, and am a part time college student, so I am not run of the mill, but I do spend some time time with younger students, and frankly, I do enjoy the company of the coeds. I do not expect or seek sexual favors, but enjoy a young and fresh look at life.

I am old, I am not, yet, dead.

I won't 'hit on' someone I think is too young. I have not been able to have kids, yet. I do hope to do so some day. Based on what I have read and experienced, I think that asking a woman my age to have kids is asking a bit much. In short, in dating I feel like the proverbial old man searching for a trophy wife or 'perv' experience... I am NOT. That is NOT what I want. I just want the normal "grow up, get married, have kiids" experience but... I am late with one (my wife and I tried, she passed away after an 8 year battle with breast cancer).

So, all that said, I restrict my active searches to women 35-45 and feel creepy about 35 year olds who respond. I actively search for about a 15 year gap (or less) meaning that I really am looking at 39 year olds.

Now, ALL of that said, if I happen to meet someone, and she doesn't have her current age tattooed on her forehead (or elsewhere) and we are having a great time and we decide to, give a 'deeper' relationship a whirl... I'd have a conversation with her before we took that step but I am not opposed (really no longer opposed, I was when I was young), to the thought of a gap in years... IF, it's a big if, the two are well matched, in spite of said gap in years.

And by 'well matched' I do NOT mean one has a lot of money, and the other a lot of naivete. I mean that they just click on a lot of levels.

I have met gals my age, or higher, who are NOT compatible. Either because they aren't ready to have a deep conversation, or because I am not physically attracted to them (or vice versa, and before your thoughts to too far in this direction, i have met some women who are smokin' hot even as far up as 70!), or... and this one is weird but it is there... culturally compatible.

Now, strangely, I have met two girls so far who are just 'old souls.' They spoke MY language, liked the same things I like. I could talk to them as a friend and NOT feel like I was a father or grandfather talking to them (I mean cultural compatibility where we truly speak the same language, despite the years). I did not 'hit on' either. One of them was old enough, mature enough really, that I made my feelings clear, and by that I mean I said I would be open to exploring the possibility. She never did answer, but she never left my life either and no, we never became a couple. We are just good friends. We respect each other and have deep feelings for each other. I think at this point we will never cross into the romantic realm though, and I am ok with that.

So, in my book it is weird to 'hit on' someone when you do NOT know them well enough to know if they are the least interested in you, or that you are more than interested at a surface (probably lust) level. It is up to both of you to determine if the number of years is a problem. You both have to talk openly and honestly about that. The thing is, that communication needs to be there even if there is NO gap in ages.

I can't answer for age but I nuts conversation would be disturbing what would be the commonality in the maturity of the conversation. I can see what the cartoon artist from playboy would make of that the girl would have $ signs and the guy steam coming out of his underwear thinking only of physical attraction.

I think it is odd when they can be your own daughter...you have to ask to meet their mother, not out of respect, but to make sure you didn't date her. I did the punk rock up until I was about 38 or so, saw a lot of people who were dating at half their age or so.

When they have kids within ten yrs of the victim, i mean the younger woman you have eyes for

In my opinion, the said man must be at least 5. Actually, age doesn't enter into it. What is most relevant is the WAY IN WHICH THE FLIRTING MANIFESTS. About half the time, in my antique experience, there is violent unconscious intent informing what the man says and informing his body language during the flirt. Hence the phrase "hit on": to hit is to commit violence.

I don't do just because we have nothing in common to relate to. 21 year olds seems like children to me... simply put... too much of generation gap.... been looking like that for many, many years. I can't see anyone in their 40's!!!! ...and then again... maturity level and complimentary factors could lead to possibility but it will be the exception and not the rule and not expected to last. Expectations on the relationship from both individuals. the 21 year old may end up being the creepy one. What is the motivation in both sides? Can of Worms Alert!!!! I like good good conversation after love or sex. flow of ideas between equals.

Is Roy Moore at it again?????

When I was 32, I was newly divorced and lonely. I went out with with a 22 year old a couple of times. After the second time it sort of felt like I was babysitting, so I never dated that young again. I know this isn't an answer to the question, but when I see rich actors and others who are in their 50s and 60s with a 20 something girl, I kind of feel sorry for both of them.

Hmmm. I find 21 year old girls very attractive, but out of my reach and beyond my interest. There’s just really no common ground. I would say outside of 40. But who am I to tell people who they should associate with? If you want to date a 21 year old, go ahead. Enjoy the inane conversation.

When my daughter was a teenager, she worked as a check out clerk at a grocery store. She used to tell me about these "old men" who would flirt with her at the check out. I asked her how old these old men were, and she got a look on her face like she was trying to calculate their ages, so I said "my age?" And says "yes!". I was around 46 at the time.

anyone above 25 M/F are adult enough to determine who they date. I would say 21 is not that fully matured. but past 25 he be could 25 and the women could be 60 or vise versa as long as it is a consenstial

I really think it depends on the maturity-levels of the people involved.

My ex-wife and I married when she was 19 and I was 29. Due to her mom's teenage pregnancy, her mom was 37 at the time. The thing is that my ex and I had a lot in common (e.g., neither of us ever partied, we were interested in academic pursuits, we were similar in politics and religion). I never had anything in common with her mother despite us being closer in age. Her mom likes to party to this very day (despite being in her 50's). My ex and I were together nearly 12 years so there is evidence that it can work. Interestingly, whereas I was nearly 10 years older than her, her boyfriend after me was nearly 20 years older than her (and two years older than her mother).

It can work under the right circumstances, but those circumstances are rare. I wouldn't discriminate against someone in their early 20's, but I have a soft limit of 25.

Lastly, I don't generally, knowingly, and actively, pursue people under 25, but I am willing to go out with someone that young who pursued me.

In my vocabulary, flirting and 'hitting on' are two entirely different things. There is no age limit on flirting. If it's creepy, it isn't flirting. If it's creepy, it may have been meant to be flirting but was delivered clumsily. Flirting is a good natured compliment of one's sexuality.

I used to think +/-4 was ideal under the idea of “in high school at the same time” rule. Then I met this woman and developed a ridiculous crush on her. She loved music that came out about a decade before I was born and popped out her first kid years before I was ready to have kids. She was also further in her career than me and living well. She’s also 8 years younger than me and I now subscribe to “old enough to go to a bar” and commonality.