"I'm dumb, aren't I?" vs "I'm dumb, ain't I?"

Words like ain't and y'all are informal but pretty common in everyday speech. "I'm dumb, ain't I?" Feels more southern USA specific, but it's totally understandable the same as "aren't I" would be.

"ain't" does not exist in standard English, despite popular informal use. "Aren't" is the standard contraction of "are not". We use many informal forms that are not standard. It is important to be aware of this distinction, as although these forms may be used in informal contexts, they would be incorrect in formal contexts. In my dialect, we use "dae" for didn't, "ay" for are not and "wor" for was not or were not. If I were to use any of these in anything except for informal conversation (or to describe informal conversation), they would be considered "wrong". Aren't I? Being the tag for the firat person is completely standard. Feel free to use "ain't" in informal contexts if you like, but be aware that many English speakers do not use this form and that it may reflect poorly on your grasp of English of you use it outside of an informal context.

Simple answer to your question is "yes, you should never use ain't". I say that since you're asking as an English learner, not because "ain't" is such a grammatical sin. "Aren't I" will be understood everywhere. "Ain't I" will be virtually useless for you unless you go to some very specific regions. And then even in those regions you run the risk of sounding like you're mocking rather than sincerely trying to use the language. So, unless you are very very very sure that "ain't" is setting exactly the tone you want, the best advice is to just never use it.

I would say both are just as valid as they are both Informal contractions used for similar purposes. Ain't is more versatile than aren't as it is a contraction of am not, is not, are not, has not, or have not while aren't is just are and not. It may seem like aren't isn't correct, but since it is informal it can be used more leniently. TL;DR They are both equally correct

I use "no it ain't" more often than "no it isn't", and the only person that I remember using ain't with I is bugs bunny in "ain't I a stinker?" I would say "aren't I" in this context, but the use of ain't depends on where you're from, for the most part. Ain't is considered AAVE, which is just a different dialect. It's not incorrect, but its use is specific to the user.

Unless you move somewhere that uses "ain't", you can't really go wrong just using standard English. I mean, you won't go wrong using standard grammar even if you move somewhere with common "ain't" usage, but I can understand wanting to fit in with the locals. You should understand it, because it's not an uncommon thing to run across in literature or music or film or TV. But you aren't required to use regional dialects in order to be fluent.

It's just like that. For whatever reason, "aren't" is the commonly-accepted contraction for "am not" in question form. "Ain't" is simply nonstandard English. It is prevalent in certain areas and completely unheard of in others, but in all cases it is considered colloquial. >As an English learner, should I never use "ain't"? Personally I would say yes, not because it's "wrong", but because it sounds awkward unless you're someone who naturally says it. I wouldn't even use it myself.

I'm dumb, amn't I?

It's a matter of classism and discrimination. The people who dictate "correct" English want to feel superior over others

As my middle school teachers used to preach, “‘Ain’t’ ain’t a word so I ain’t gonna say it.” It’s not accepted as a real or proper word, and would be seen as “hillbilly” or lower class/uneducated

Yes, never use "ain't." 

"Ain't" is a dialect word. It's used in multiple common dialects, but it will still sound awkward at best or insulting at worst when used by someone not otherwise speaking that dialect.

my grandma once said to me, "dont say aint 3 times a day cuz aint aint no word." but i dont remember not to lol.

As others have said, it's a bit of a class thing. People who don't speak properly and are generally poorer will be more prone to say 'ain't.' My family was lower middle class, trying to move up, so it was drilled into us constantly to NEVER use the word. I literally never use it in speech or writing.

I don't think "aren't I" is totally correct either, but it seems to be considered less incorrect than "ain't I". Totally correct would be "am I not", but that would be pretty formal and less common. Unfortunately "amn't I" doesn't exist.

Second one sounds more truthful. 

Ain't ain't a word.

In Ireland most people would say "I'm dumb, amn't I"!

I interpret the former as a solemn realization that prompts personal change and the latter as a sarcastic reaction after a minor mistake

I think as english speakers we are those most used to hearing non-native accents, but still I would personally cringe a little if I heard someone use 'ain't' who obviously isn't a native speaker because it sounds really forced

We use "amn't I" where I'm from. Other people eschew the obviously correct grammatical form for some reason.

Ain’t isn’t wrong but it just isn’t formal English. There is nothing wrong with using it in speech but I would advise against using it in formal writing like work emails and the like.

I would never say aren't I or ain't I in this situation, probably phrase it differently like "oh my god am I not the dumbest person ever?" or "oh I'm so stupid" or something. 

As an English learner, I would recommend that, for the time being, erase "ain't" from your expressions.

To be honest, both of those sentences feel weird to me. I would just say "I'm dumb" and let the other person respond.

these two phrases have different meanings "i'm dumb, aren't i?" = i'm realizing i might be dumb, can you confirm? "i'm dumb, ain't i?" = we already established i was dumb and you're talking to me like i'm smart

Conversationally, they’re fine. Dumb is informal anyway, if you were being formal you’d probably say “I’m a fool aren’t I?”. So try this: “I’m dumb int ah”, and “I’m dumb ay I!” Both English (as in 🏴󠁧󠁢󠁥󠁮󠁧󠁿) expressions!

The best answer would be "amn't I" but the world just isn't ready for that yet (Don't say this)

I recommend that learners never use ain't. It's a strongly dialectal word, and if you use it you're likely to sound like you're mocking the accents/dialects that use them. They're traditionally associated with poorer and less educated Americans, so an outsider using it is likely to land wrong.

Ain’t is pretty much just a regional thing. It’s not standard English, and it would be considered informal, but it’s still acceptable

While ain't is technically more correct, it having come from "amn't", it came to be seen as dialectical (probably by misuse of it with other persons/numbers), so it's not something I would use and it's not considered proper any longer. If I were ESL I might only use it with certain groups who already do.

Both are technically fine, there are cultural/subcultural associations involved. So it will depend on whom you are speaking to.

>should I never use "ain't"? Your sentence here is grammatically correct but it does sound a little awkward. I’d use something like “should I ever use ‘ain’t’?“ or “should I avoid using ‘ain’t’?“

Native speaker here. California. As a child, we were told ain't is uneducated and don't use it or people will think badly of you. 40 years later, I honestly don't know it I've ever used it. I would tell any English learner the same thing - to know what it means but not say it unless you are living somewhere that it's common and doesn't carry the negative stereotype.

Ain't is quite regional or class dependent and depending on where you are there will be cultural associations that come with using it. For example, in the UK it is often seen as a sign of low class or poor education e.g. petty criminals and domestic servants are often depicted in literature as saying ain't ("I aint done nothing wrong guv"). In the US it is more dependent on region being more common in the southern states. It is also a feature of AAVE. Use it if you want but native speakers will think it weird that you are saying it when you are obviously not of the stereotype they associate with the word.

The problem is that "ain't" isn't a real word. It is slang among a small number of native speakers. I have never used it, or heard anyone use it in person, so I would recommend against using it in casual speech. It will probably sound unnatural.

I would say just don't use "ain't"