Battery cycles

It's not a matter of remaining cycles. The phone doesn't suddenly drop dead at 500 cycles like the one horse shay; it's an approximation. The Battery Health is a much more useful measure, as it takes into consideration more than just cycles.

If you have a Mac, download CoconutBattery (a free program that has been available for Mac’s for a decade or more). With an iOS device plugged into a Mac, CoconutBattery will display the battery health in terms of design capacity, current capacity, number of cycles, etc.

Oh, that's disappointing to hear since it is supposedly compatible with iOS 12 and MacOS 10.14. Hopefully it is something they can fix. While I have never fixated on that app or any battery health app with my devices, I have always liked CB just for its legacy and simplicity.

Go to an Apple Store. They run a test to your phone that tells you the "Battery Health" of your phone. If the battery capacity of your phone is already too low, they will offer you a battery replacement (for an amount of money of course). If your battery capacity is "normal" they will tell you.

They wont charge you for this test.

If you have never changed the battery of that iPhone 5S, it's almost sure you need a new one.

Are you asking because you have battery issues?

With iOS 12 the cycle count is no longer accurate.

This is the only way that I have found so far to get battery cycles on iOS 12