<prompt> Human: I am a Johnny-come-lately to listening to my grandmother and budgeting, taking care of my money, investing in retirement, etc. Better late than never, right? I finally started to learn finance, thanks to generous people answering questions in places like this and Bogleheads.So Ive learned quite a lot now, and consequently, I want better better credit cards. The only credit card I had for a very long time was the first card I ever applied for, which has a terrible APR, mostly because I signed up for it as a college student. It has a high credit limit by my standard, which may or may not be average, increased a couple of times over the years. It has eleven years of credit history to go with it. However, as the subject suggests, the APR is ridiculously high.I somehow miraculously managed to make it through my twenties living paycheck-to-paycheck and still come out of it with excellent credit. I know I can get a new card with half the APR and great rewards. But Im loathe to close an 11-year-old account with a high line of credit. I dont know how big of a hit that would be to my nice credit rating, but I fear it would be huge.I confirmed with the card issuer that I can leave the account open indefinitely, and it will only be marked inactive, meaning Id have to call and reactivate it to use it again. Right now, thats my best option, but Im wondering if anyone has tried to get the APR on a credit card lowered.If thats not possible, how about this: if you have one type of card, is it possible to upgrade to a better card? In effect, the new card replaces the old one, but the account remains open, so you dont lose the history? Like, switching from an Amex Green to an Amex Blue? Not my card; just an example.I realize I could ask these questions of the bank, but I dont want to let them know what Im thinking of doing, because Im illogically paranoid.  <response>: I would say that you should definitely not close the account as it will negatively effect your average credit length. I would suggest just using it and purchasing only small things and paying off the balance in total each month. This will avoid paying any interest.The negative aspect of high interest cards are only relevant if you carry balances over from month to month.Also try creditkarma.com I dont see the benefit of turning the card inactive. 