iPhone Battery Life Estimator 2026 - How Long Will Your Battery Last?
How long will your iPhone battery last before it needs replacement? Use our free estimator to find out based on your current battery health, daily usage, and charging habits.
Apple recommends replacing your iPhone battery when Maximum Capacity drops below 80%. At this point, you may experience reduced battery life, unexpected shutdowns, or performance throttling.
Our calculator uses real-world degradation data to estimate how many months you have before reaching that threshold. Enter your information below to get your personalized estimate.
🔋 Battery Life Estimator
Find out how long until your battery needs replacement
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How the Battery Life Estimator Works
Our calculator uses a model based on typical lithium-ion battery behavior:
Base Degradation Rate: Batteries lose capacity over time regardless of usage. Light users may see around 0.4% degradation per month, while power users can experience over 1% per month.
Charging Habit Impact: How you charge affects battery longevity. Deep discharges (letting your battery hit 0%), fast charging heat, and keeping your battery at 100% for extended periods accelerate wear. Good habits can reduce degradation by up to 30%.
The Formula: We calculate your monthly degradation rate based on usage intensity and charging habits, then divide the percentage points remaining (current health minus 80%) by that rate.
iPhone Battery Degradation by Usage Pattern
Here is how different usage patterns affect battery lifespan:
| Usage Level | Screen Time | Monthly Loss | Time to 80%* |
|---|---|---|---|
| Light | 1-2 hours | ~0.4% | ~50 months |
| Moderate | 3-4 hours | ~0.6% | ~33 months |
| Heavy | 5-6 hours | ~0.85% | ~24 months |
| Power User | 7+ hours | ~1.1% | ~18 months |
*Starting from 100% health with average charging habits. Poor charging habits can reduce these estimates by 30-50%.
How to Make Your iPhone Battery Last Longer
Based on our research and Apple's recommendations, here are the most effective ways to slow battery degradation:
Keep it Cool: Heat is the biggest enemy of lithium-ion batteries. Avoid leaving your iPhone in hot cars, direct sunlight, or under pillows while charging. If your phone gets warm during charging, remove the case.
Enable Optimized Battery Charging: Go to Settings > Battery > Battery Health and enable this feature. iOS learns your daily routine and waits to finish charging past 80% until you need your phone.
Avoid Deep Discharges: Letting your battery drop to 0% regularly puts stress on battery cells. Try to plug in when you reach 20-30% instead.
Use Slower Charging When Possible: Fast charging is convenient but generates more heat. For overnight charging, a standard 5W or 10W charger is gentler on your battery.
Monitor Your Health Monthly: Check Settings > Battery > Battery Health regularly. Catching unusual degradation early lets you adjust habits before significant damage occurs.
Get Accurate Battery Health Tracking
Want more than just an estimate? Battery Health Pro tracks your actual battery health over time and shows you exactly how your habits affect degradation.
Frequently Asked Questions
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With average usage and good charging habits, most iPhone batteries retain 80% capacity for about 2-3 years (500 complete charge cycles). Heavy users or those with poor charging habits may see 80% capacity in 18 months or less.
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At 80% Maximum Capacity, your battery holds 20% less charge than when new. A phone that originally lasted 10 hours might now only last 8 hours. Apple considers this the threshold where replacement provides meaningful improvement.
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Our estimator provides a reasonable approximation based on typical lithium-ion behavior. Actual results vary depending on factors like ambient temperature, specific usage patterns, iOS version, and individual battery chemistry. For precise tracking, use an app like Battery Health Pro.
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Generally, no. Most users can continue using their iPhone comfortably above 80%. However, if you experience frequent unexpected shutdowns or significant performance issues, earlier replacement may be worthwhile.
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High brightness increases power consumption, which means more charge cycles over time. However, the direct impact on degradation rate is minimal compared to factors like heat exposure and deep discharge cycles.
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Go to Settings > Battery > Battery Health on your iPhone. You will see Maximum Capacity (your health percentage) and Peak Performance Capability (whether throttling is active). On iOS 26+, you can also view your cycle count.
