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Battery & Hardware · 5 min read

How to Check iPhone Battery Health & When to Replace Your Battery

By iPhone Update Editorial Desk · Reviewed September 19, 2026 ·5 min read
DIRECT ANSWER

Check battery health in Settings → Battery → Battery Health & Charging. Apple recommends replacement when Maximum Capacity drops below 80% within 500 charge cycles (1,000 on iPhone 15/16). A "Service" alert means replacement is recommended.

1. Check Battery Health

  1. Open Settings → Battery → Battery Health & Charging.
  2. Maximum Capacity: Shows the current chemical capacity relative to when the battery was new. 100% = full factory capacity. 85% = the battery holds 85% of its original charge.
  3. Peak Performance Capability: If this shows "Your battery is currently supporting normal peak performance," your battery is healthy. If it mentions performance management, your battery may be throttled.
  4. Cycle Count (iPhone 15 and later): Shows how many complete charge cycles (0% → 100%) the battery has undergone.

2. Understand the Numbers

  • 95–100%: Excellent. No action needed.
  • 85–95%: Good. Normal degradation for a 1–2 year old phone. Battery life is slightly reduced but still acceptable.
  • 80–85%: Aging. You may notice significantly shorter battery life, especially during cold weather or intensive tasks.
  • Below 80%: Replace soon. Apple's battery warranty covers replacement if capacity drops below 80% within 500 cycles (iPhone 14 and earlier) or 1,000 cycles (iPhone 15 and later).
  • "Service" alert: Apple explicitly recommends battery replacement. Performance management may be active.

3. Get Your Battery Replaced

  • Apple Store or AASP: Book a Genius Bar appointment or visit an Apple Authorized Service Provider. Typical cost: $79–$119 depending on model (prices vary by region).
  • AppleCare+: If you have AppleCare+ and battery health is below 80%, replacement is covered at no additional cost.
  • Self-Service Repair: Apple's Self-Service Repair program allows experienced users to purchase genuine battery kits and perform the replacement themselves.

4. Maximize Battery Lifespan

  • Optimized Battery Charging: Enable in Settings → Battery → Battery Health & Charging. This learns your routine and delays charging past 80% until you need it.
  • Charge Limit (iPhone 15+): Set an 80% charge limit to reduce chemical stress on the battery.
  • Avoid extreme temperatures: Lithium-ion batteries degrade fastest above 35°C and below 0°C.
  • Use genuine or MFi-certified chargers: Non-certified chargers may deliver inconsistent voltage.

Do not do these

  • Battery health percentage may drop 1–2% after a major iOS update due to recalibration — this is normal, not damage.
  • Do NOT obsessively check battery health daily. The number changes slowly and checking frequently serves no purpose.
  • Third-party battery replacement services may use non-genuine cells that lack Apple's battery management integration.

Questions this page actually answers

Does a new iOS update damage my battery?

No. Updates may temporarily increase battery drain (24–72 hours) due to background indexing and ML model compilation. A 1–2% Maximum Capacity drop is recalibration, not damage.

How many charge cycles does an iPhone battery last?

Apple designs iPhone batteries to retain 80% capacity at 500 complete cycles (iPhone 14 and earlier) or 1,000 cycles (iPhone 15 and later). Most users complete 250–400 cycles per year.

Is it bad to charge my iPhone overnight?

With Optimized Battery Charging enabled, no. iOS learns your schedule and holds the charge at 80% until shortly before you wake up, minimizing time spent at 100%.

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Sources

Prepared by the iPhone Update Editorial Desk. Independent technical reference. Not affiliated with Apple Inc.