93% is not bad. What is your concern? Are you noticing short usable duration?
I wouldn't start being concerned until it was down to ~80%... and then also if I wasn't getting the duration I would like to get.
Your battery should last a couple of years at least, unless it's faulty or damaged.
You can bring your iPhone in to Apple and have the battery replaced if you're that concerned.
iPhone battery replacement - Apple Support: