Your iPhone’s True Remaining Battery Life

Apple is lying to about your iPhone’s true remaining battery life. In fact YouTube and Tech Bros lie to you each time they discuss this with a clickbait video regarding your battery life. He is why. In photo 1 is the battery health noted by Apple. On my iPhone 17 Pro Max it states I have 207 charge cycles and it’s at 100% of its capacity.

The second photo is from the Battery Stats Shortcut that uses the phone’s analytics file to determine a few things.

• The iPhone’s original maximum Capacity
• The iPhone’s Nominal Charge Capacity
• The iPhone’s Cycle Count

Noticing first that my iPhone’s original maximum capacity was 5206 mAh, while real-world specs say it should be 5088 mAh. My charge capacity is 4981 mAh. The math Apple does is it takes the 4981 and divides by 5088, I get 97.90% remaining nominal charge capacity. If divided by the original maximum capacity the remaining nominal charge is 95.68%

Why the difference and why is it no 100%? In my search of Claude to better understand this it came out with this response and it is close enough to an answer I could find.

Phone batteries vary in actual capacity because manufacturing tolerances in electrode coating thickness, electrolyte fill volume, winding tension, and material purity all shift how much active material ends up in each cell. Manufacturers publish a “typical” capacity that represents the average of the distribution and a lower “minimum” capacity that nearly every cell clears, but the number in your phone’s firmware is a fixed design constant identical across all units of that model. That mismatch between a fixed reference number and a real measured cell is why brand new iPhones can read 99%, 100%, or 101% health right out of the box

Basically not all batteries have the same capacity upon completion of the manufacturing process. In the end my statement above about Apple lying about its capacity remains. My battery is not at 100% charge capacity. Again used Claude for an explanation.

A phone battery works by shuttling lithium ions back and forth between two sides of the cell, but every time you charge it, a few of those ions get permanently glued into a thin crusty film on one side and can never move again. That film keeps slowly thickening with use, and on top of that the electrode materials crack a little from swelling and shrinking each cycle, so some material gets cut off from the circuit entirely. The battery also ages just from sitting around, especially when it’s hot or kept at a full charge, so time alone costs you capacity even if you never use the phone. Most of the damage happens early and then slows way down, which is why losing about 4% after 206 charges is normal and actually pretty healthy.

You can determine your actual capacity by using the Battery Stats Shortcut.

To use simply download here https://www.icloud.com/shortcuts/2bed635a933046d7a6ac43fd2b17a6b0.

Go to Privacy & Security > Analytic & Improvements > View Analytics Logs. Find the file that has the current dates and use the one says something like this Analytics-25026-09-01-180009.000.ips.ca.synced. You may see two labeled that, one will give you results one will not. If you can’t get a number just keep lookin for the version number that is similar. Good Luck!