iPhone 16 pro charging past the set 90% limit

This is normal and expected behavior. Apple notes this in several support articles.

>>If you have Charge Limit set to less than 100 percent, your iPhone will occasionally charge to 100 percent to maintain accurate battery state-of-charge estimates.<<

About Charge Limit and Optimized Battery Charging on iPhone - Apple Support

The iPhone has to do this so it can calibrate to 100% battery capacity. It’s normal. 

Please see: About Charge Limit and Optimized Battery Charging on iPhone - Apple Support

Especially: “If you have Charge Limit set to less than 100 percent, your iPhone will occasionally charge to 100 percent to maintain accurate battery state-of-charge estimates”.

Read through the posts, it's already been explained.

Yesterday was the first time it charged to 100% yet nothing was changed with the limit on settings or the way I charge the phone

Normal and expected for the phone to charge to 100% "occasionally". The big question is how often is "occasionally"?

When I tried this, I found that "occasionally" was about 3-4 times a month. Other users report that phone charges to 100% more often and some report less often.

Personally, I think setting the charge limit to 80% or 90% etc is more of a gimmick than anything else, but that is for another discussion.

Hi, I’ve just experienced the same problem. I usually set my charging limit ant 80% and I don’t charge my phone overnight but it seems that today my phone has decided that it will charge to 100%. Usually I wouldn’t think much of it but hopefully this is a one time thing because I want to at least keep the battery health on this phone at 100% for 5-6 months. Glad to see that I’m not the only one experiencing this.

Plss explain me that

I experienced the 91% within the limit set to 90% one time. I don’t know why!

I set my phone charging level at 85% and last time it exceed the limit to 87% without changing the battery charging level

This is normal behavior and occasionally will happen.