If your iPhone battery doesn’t seem to last as long as it used to, Apple has a few tools that can help. Recent models include smarter charging options to slow battery wear and new ways to check the overall health of your battery — including how many full charge cycles it’s been through. Here’s how to use them, and how to tell when it’s time for a replacement.
Charging optimization
Apple’s Optimized Battery Charging feature helps preserve your battery’s long-term health by learning your daily routine. When enabled, your iPhone will delay charging past 80% if it predicts you’ll be plugged in for a while — for instance, overnight — so it doesn’t sit at full charge unnecessarily.
You can also choose to limit charging to 80% at all times. This goes beyond the smart delay system and ensures your battery never fully charges, sacrificing a bit of daily endurance to further extend its lifespan. It’s a great option if you spend most of your day near a charger or don’t mind a slightly shorter runtime between top-ups.
To adjust these settings, open Settings > Battery > Battery Health & Charging > Charging Optimization. You’ll see three choices: Optimized Battery Charging, 80% Limit, or None if you prefer not to limit charging at all.
Check your cycle count
You can now view your iPhone battery’s cycle count, which indicates how many complete charge-and-discharge cycles it has experienced. A cycle represents 100% of total battery capacity used — though this can happen over multiple partial charges. For example, draining 50% one day and another 50% the next counts as a single cycle.
This figure gives a clearer sense of your battery’s condition than its age alone. To find it, open Settings > General > About and scroll to the bottom. You’ll see your battery’s Cycle Count and Manufacture Date listed together.
When to replace your battery
Even with good charging habits, every lithium-ion battery eventually degrades. As capacity drops, your iPhone won’t hold charge as long and may reduce performance under heavy load to prevent sudden shutdowns. You can check this under Battery > Battery Health & Charging, where your Maximum Capacity percentage is displayed.
If that number falls below about 80%, it’s usually time to consider a replacement. Apple or an authorized repair provider can fit a new battery for far less than the cost of a new iPhone — and it can make your device feel like new again.