My iPhone battery isn't working properly. Is it the charger or the phone?

I usually charge my phone while I sleep at night. It charged to full battery on Tuesday night and was fine. I plugged it in last night (it was dead), it charged to 4%, turned on, and then stopped charging. I assumed it was the charger and that it had just broken, so I just thought I'd buy a new charger. Then I reset the charging outlet today and plugged it in again and it did the same thing (charged to 4%, turned on, and stopped charging).Is it the charger or my phone that's messed up?

It just may be your phone.

I'm no expert, but you can try to fiddle around with it to see if it's merely a glitch. I would avoid taking it in unless you've done everything you can to stop it. Like turning it on and off when it reaches 4% or leaving it "charging" even if it says it doesn't charge and see if it still charges or not…

Batteries are actually one of the easiest parts to replace on an iphone (the back screen/backing is the easiest) and they actually do come really cheap. I believe 5$ cheap. I had a cracked screen and I opened my iphone (with a screwdriver the proper way) and had to take it apart to replace the front. There are youtube videos for everything. I think you should at least check it out by going on youtube and seeing how to replace an iphone battery (and they usually give a link as to where you can buy an iphone battery). I wouldn't suggest actually doing this unless you are sure it's the battery that's the problem. I think maybe you can bring it in to either Apple or your phone company and see what they say is the problem. If they say its a battery… DO NOT let them fix it for you because I guarentee you they'll charge 100-200$ when its a 5$ fix. I mean my cracked screen is a 200$ charge but the glass, scredrivers, ect. All was just 10$ and was done easily and nicely by myself.

It could be just a weird software glitch though that's forcing your phone to reject the charge or another hardware problem that is not from the battery that I wouldn't know how to fix. Like I said, try to fiddle around with it.using different outlets/chargers. Or turning it off and on at certain periods of the charging stage and if you really are hitting a wall, ask someone to look at it and see what they say before replacing the phone or anything like that.