Battery health above 80 percent is considered good for an iPhone
Battery health is a percentage that tells you how much charge your iPhone's battery can hold compared to when it was new. You can find it in Settings > Battery > Battery Health & Charging. A reading of 80 percent or higher means your battery is in good condition and should power your phone through a full day of normal use.
Apple designed iPhone batteries to retain 80 percent of their original capacity after 500 complete charge cycles. One charge cycle means using 100 percent of your battery's power, whether that happens in one day or spread across several days. Most people reach 500 cycles after about two years of regular use, which is why 80 percent is the threshold Apple uses to define a battery that has aged normally.
Battery health below 80 percent does not mean your phone will stop working. It means your battery drains faster than it did when new, and you may notice your phone shuts down unexpectedly when the battery percentage is still above zero. This happens because the battery cannot deliver the power your phone needs all at once, even though it still holds some charge.
Key Takeaways
- Battery health of 80 percent or higher indicates your iPhone battery is aging normally and should last through a full day of typical use.
- Battery health below 80 percent means your battery drains faster and may cause unexpected shutdowns, but your phone will still function.
- One complete charge cycle equals 100 percent of battery use, and reaching 80 percent health typically takes about two years of regular charging.
- You can see your battery health percentage in Settings > Battery > Battery Health & Charging on any iPhone running iOS 11.3 or later.
- Factors like heat exposure, frequent fast charging, and letting the battery drain completely can lower battery health faster than normal aging.
How battery health percentage is measured
Your iPhone measures battery health by comparing how much charge the battery holds now to how much it held when brand new. The phone tracks this through a chip inside the battery that monitors voltage and chemical changes over time. This measurement is not a prediction of future performance—it is a snapshot of the battery's current state.
The percentage you see is called maximum capacity. If your battery shows 85 percent health, it means the battery can now hold 85 percent of the charge it could hold on day one. The remaining 15 percent represents permanent chemical changes that happen inside all lithium-ion batteries as they age, regardless of how carefully you use your phone.
When battery health drops below 80 percent
Once your battery health falls below 80 percent, you will likely notice your phone drains faster during the day. A battery at 75 percent health might lose 5 to 10 percent of its charge per hour of active use, compared to 3 to 5 percent when the battery was new. This means you may need to charge your phone more often or carry a charger with you.
Below 80 percent, your phone may also show unexpected behavior. iOS includes a feature called peak performance management that automatically reduces your phone's processing speed when the battery cannot deliver enough power quickly. This prevents sudden shutdowns, but it makes your phone feel slower during demanding tasks like gaming or video recording. You can turn this feature off in Settings > Battery > Battery Health & Charging, but doing so increases the risk of unexpected shutdowns.
At around 50 percent battery health, many people choose to replace the battery because the phone becomes noticeably slower and drains too quickly for daily use. Apple offers battery replacement for a flat fee (typically $69 to $99 depending on your iPhone model), which is usually cheaper than buying a new phone.
Factors that lower battery health faster
Heat is the single biggest factor that degrades battery health. Leaving your iPhone in a hot car, using it while charging, or exposing it to direct sunlight for extended periods speeds up chemical breakdown inside the battery. Even temperatures above 95°F (35°C) can cause noticeable damage over time.
Frequent fast charging also wears batteries faster than standard charging. Using a high-wattage charger every day creates more heat inside the battery than a standard 5-watt charger. If you fast-charge regularly, your battery may reach 80 percent health in 18 months instead of two years.
Letting your battery drain completely to 0 percent and then charging it back to 100 percent repeatedly is harder on the battery than keeping it between 20 and 80 percent. However, occasionally draining your battery completely does not cause significant damage—it is the pattern of frequent deep drains that matters.
How to check your battery health right now
Open Settings on your iPhone and tap Battery. Then tap Battery Health & Charging. You will see a percentage labeled "Maximum Capacity" and a condition status below it. The condition status will say "Normal" if your battery is in good shape, or it may show other messages if there is a problem detected.
If your iPhone is older than iOS 11.3, the battery health feature is not available. You can check your iOS version in Settings > General > About. If you need to update, go to Settings > General > Software Update.
The battery health percentage updates automatically as your phone monitors the battery. You do not need to do anything to refresh it—just open the settings page and you will see the current reading.
What to do if your battery health is low
If your battery health is between 70 and 80 percent, your battery is still usable but aging faster than normal. Consider whether the phone's performance meets your needs. If you are happy with how it works, there is no urgent reason to replace the battery yet. If you notice the phone shutting down unexpectedly or draining too fast, a battery replacement will restore performance.
If your battery health is below 70 percent, you have two main options: replace the battery through Apple or an authorized repair provider, or replace the phone. Battery replacement takes about an hour at an Apple Store or authorized shop and costs a flat fee. A new phone costs significantly more but also gives you a newer processor and updated features.
Before replacing the battery, try adjusting your charging habits. Enable Optimized Battery Charging in Settings > Battery > Battery Health & Charging. This feature learns your charging patterns and slows down charging to 80 percent overnight, then finishes the last 20 percent right before you wake up. This reduces stress on the battery and can slow further degradation.
Frequently Asked Questions
Is 85 percent battery health good?
Yes, 85 percent is considered good battery health. It means your battery is aging normally and should power your phone through a full day of typical use. Most iPhones reach this level after about 18 months of regular charging.
Can I improve my battery health percentage?
No, battery health percentage cannot be improved once it has declined. The percentage reflects permanent chemical changes inside the battery. You can slow future degradation by avoiding heat, using standard charging instead of fast charging, and keeping the battery between 20 and 80 percent when possible, but you cannot reverse damage that has already occurred.
What does "condition: service" mean?
If your battery shows "Service" as the condition status instead of "Normal," it means Apple has detected a problem with the battery that is not related to normal aging. This could indicate a defect. Contact Apple Support or visit an Apple Store to discuss replacement options, which may be covered under warranty.
Does closing apps or turning off background refresh improve battery health?
No, those settings do not affect battery health percentage. Battery health is determined by the battery's chemical condition, not by how you use your phone. Those settings only affect how fast your battery drains during the day, not the maximum capacity it can hold.
How often should I charge my iPhone to keep battery health good?
Charge your iPhone whenever it is convenient—there is no perfect charging schedule that preserves battery health. Modern iPhones are designed to handle daily charging. The most important factors are avoiding heat and not letting the battery drain completely very often. If you want to minimize degradation, enable Optimized Battery Charging and avoid using your phone while it is charging.