I don’t know mine. I have to look at my card whenever I purchase something online. Why? It seems to me that I type or say my credit card number as much as I type or say my phone number, and I would consider it totally weird not to have my own phone number committed to memory.
On the other hand, my youth was spent in an environment where you had to recall your own phone number all the time, because it wasn’t programmed into your phone and you had to dial it every time you wanted to use it. So the followup question for those readers who grew up in the cellphone era is: do you know your own phone number by heart?
Quomodocumque 
I used to know my credit card number, but I was issued a new number after a security breach and didn’t learn the new one.
I’m a little bit confused about the phone thing, though. I never had to dial my own phone number to use my phone, even before cell phones. But anyway, I know my cell phone number, and I don’t recall ever meeting anybody who had a phone but didn’t know the number. After all, it’s still the case that if two people want to communicate by phone for the first time, at least one of them has to know their own number. I guess you could look up your own phone number on your phone, but it makes things easier to just know it. (Of course, one could say the latter for credit card numbers, too.)
I don’t know any of my credit card numbers, though I think I know the last four digits of many of them. I know my own cell number, but learned just yesterday that my wife doesn’t know my number. (She and I both know hers.)
I don’t know any of my credit card numbers. I do know my phone numbers, but (a) it took me a while to learn one of them and (b) I takes me a second or two to retrieve any of them from memory and I’m never completely sure I’ll be able to. But I think I’m asked my phone number more often than my credit card number. I guess I don’t buy much online.
I’m the same – I learn my credit card number after typing it a few dozen times, but then I lose the card or there’s a fraudulent charge and it takes a long time to learn the new number. It helps that the first 6 digits are constant from one card to the next. Right now I’m in the don’t-know phase. And I have never learned a debit card number.
I got my current cell phone number at the same time I moved, so I had to write it on a dozen forms right away which learned me it. But I don’t know my office phone number.
Jordan, do you know your wife’s cell phone number? (Obviously knowing anyone else’s would be a throwback too far.)
I know both. Possibly it’s because I buy a lot of things online.
I know my card number. But I remember the specific moment when I realized that it was *possible* to memorize it, and to use it without having the card physically present.
Just writing that down looks weird: of course it’s possible! Nevertheless, it was a revelation at the time. No one had taught me that memorizing a card number might be a useful thing to do. I’ve seen people look surprised when I’ve recited the number down the phone without getting the card out of my pocket, and your post also gives me the pleasant sensation that I’m not the only one for whom this wasn’t an automatic act.
Born in ’84 here. Know my phone number, don’t know my credit card number. Note that I recently changed credit cards due to moving all my money from banks to credit unions (which I heartily recommend). I didn’t have the previous card memorized either.
Interesting side-fact: I can still recite phone number for the library where my parents worked while I was growing up.
Like Adam, I sometimes know my credit card number, depending on how long it has been since it was last changed. Currently, I don’t.
Yes, I know my CC number and its expiration date and security code. I did not memorize them; I just remember them.
I don’t know my credit card number which I have had for years. I know my own land line number which I have had for over 30 years and my mother’s phone number which was also my phone number when I was a kid, but I can never recall my sibling’s numbers. Sadly, I know the phone number of my pharmacy. I’ve been retired for two years but I still remember my office phone number, although it just took me about 5 seconds to recall it. I know my SS number, but when asked for the last four digits I have to run through the entire number in my head in order to retrieve those four digits. I know my license plate number, which I’ve been told is especially weird.
I don’t think I quite grew up in the cellphone era — I got my first cell phone in college. I remember having a pager in high school and feeling awfully cool.
Anyway, I am pathologically incapable of remembering numbers. I don’t know my cell phone number or my credit card number, and I have to think pretty hard if I want to remember my age or birthday.
I also have a difficult time remembering random numbers. That I can remember any at all is remarkable. When I was in very early grade school I approached remembering the multiplication tables by memorizing the squares and thinking, for example, very rapidly in my head, 8 x 9 = 8^2 + 8 = 64 + 8 = 72 (so I was inventing very elementary algebra by myself). At the moment I have another memory challenge. After 25 years, I’ve once again started playing with a classical guitar. I have to learn all over again the motor skills and how to commit the execution of a piece to memory. This is not easy at my age, but I’m starting to make some progress.
Memory became a temporary critical problem for me in middle age. That was when a rare and long undiagnosed and untreated problem in my antibody subsystem (hypogammaglobulinemia) started to become an overwhelming problem with chronic upper respiratory and other infections and my short term memory deteriorated alarmingly (probably due to chronic cytokine activation). Fortunately, I’ve been able to mostly recover from that episode.
I suppose I also find it particularly easy to memorize numbers. Individual digits or combinations of digits have a certain flavor to me, and I notice numerical properties of digits or combinations of digits that help me remember what a given number “feels” like, to be a little vague.
To be more concrete, the number of my house is 2418, which I remember roughly as follows: 24 and 18 are both multiples of 6, one of which is 6 less than the other, and the whole number begins with a 2. Not terribly efficient, but it works.
Sometimes I also build muscle memory of typing the number out (not on a keypad but on the top row of my keyboard). That’s how I have my secure password memorized as well as my credit card number and my SSN.
Yes, I also know my credit card number including security code and expiration date. I usually remember a number that I have to use on a almost daily basis after a few times. I also know my current cell phone number and the last one. That confuses me sometimes – in the first two years after changing my cell number I told people quite often my old number. Occasionally, I still mix up those two numbers.
I’m approximately your age, and I stopped bothering to memorize my phone number a few phone numbers ago — around the time I got a cell phone. Hey, my phone tells me my number (both home and cell number), and I always have it with me. So why waste brain space on them? And I have certainly never memorized any of my credit card numbers. That said, I have quite a number of computer-generated-nonsense-word passwords memorized.
I do not have my credit card number memorized, but I do have my phone number memorized. (Qualifier: I live in grad dorms and the room comes with a landline, the number of which I do /not/ have memorized.)
I got my first cell phone in 6th grade (and was one of the very few people who had one at that point), but I don’t consider myself as “growing up in the cell phone era” because until about 10th grade, people used landlines all the time and I guess I feel the same way you do about not knowing ones own number. I do know the numbers of my sister and parents, but that’s cheating a little because they only differ from mine by one number.
Relatedly: I memorized my student IDs in both undergrad and grad school from the beginning because there are so many things where it’s relevant to have them. I also have my social security number memorized, something I’ve found out not everyone does. (My officemate, who memorizes numbers easily, told me a story about how he accidentally saw a friend’s SSN while at the bank with her and couldn’t get it out of his head for the next year even though he really didn’t want to know it.)
Regarding not memorizing your credit card number perhaps it comes from a kind of “privacy/honesty reflex”, pudeur, or good-behavior (unconscious) assumption, like buying organic (bio in EU) food, or helping people in (more) need. It is perhaps useful to be shy about such things, to avoid awkward situations like accidentally looking at some stranger’s card number, which may violate her/his privacy, or at least which s/he/we may feel that way and resent.
Those behaviors must be quite rigid because they occur in situations we cannot (easily) prepare much for. If you go to a supermarket you are not going to think 10 min before what to do in every possible scenario, or if you use public transportation, etc.
People do not communicate freely their credit card numbers, for obvious reasons, so by extension/association/rigidity they may not even want to think about their own when they use it. While phone numbers may be freely chatted on, they can be chosen sometimes, argued upon. Also they are shorter in most countries and perhaps more designed-to-be-remembered.
So who can recall her/his card numbers will be a mix of factors, as presented in the comments here.
PS: Personally I remember some of my card numbers, and my phone number, but I have been juggling with like 20 cards lately (moving, remembering my wife’s, etc.) which put me pressure to remember them while also making it harder.
Numbers/IDs that I have memorized
my cell number – on a kabillion forms and always needed when you call customer service for anything
my wife’s cell number (same as mine, just one number transposed)
my SSN
my wife’s SSN
my undergrad ID number
my needlessly complicated current university ID number
I’m kind of surprised that I don’t know my cc number. I don’t do much shopping online though.
I also still have my parents’ and wife’s old phone numbers memorized despite the fact that I haven’t had to physically dial them in nearly a decade.
Yes, my credit card is 4960 3217 5820 0332, and the security code is 623
The only car license-plate number I can recall is that of the first one I owned. I don’t remember my credit card numbers. I know my home and work land-line phone numbers but not that of my cell phone.
There was a time when I knew the Intel 8008 instruction set (machine code, not assembler mnemonics), but no more.