Glossary · 用語
Cycle count.
One battery cycle equals one full equivalent discharge of your MacBook’s battery. Discharging from 100% to 50%, then charging back, then discharging to 50% again counts as one cycle — not two.
Cycles are cumulative. They don’t reset. macOS counts fractional usage in firmware: if you use 30% of capacity each day for four days, that’s roughly 1.2 cycles total. You never have to track this manually.
Modern MacBooks (Apple Silicon, plus most 2018+ Intel models) are rated for 1,000 cycles before capacity is expected to drop below 80% of design. Older models were lower — see cycle-count threshold for the per-model list.
One subtlety: the cycle count itself doesn’t damage the battery — it’s a measurement, not a cause. What actually ages cells is time at high voltage and heat, not the counter ticking up. That’s why a charge limit (Sensei or macOS Sequoia’s built-in) extends calendar lifespan even when the cycle count keeps climbing.
How to check it on Apple Silicon: System Settings → Battery → click the ⓘ next to Battery Health. The current cycle count appears next to “Maximum Capacity.”