# Why does my Mac still charge to 100%? > Usually because macOS charges to 100% now and then to keep its battery estimates accurate. Shutdowns, Optimized Charging and app conflicts come next. URL: https://chargeberry.app/guides/why-does-my-mac-charge-to-100/ Author: Ayesha Gagan (https://chargeberry.app/about/) Published: 2026-11-06 · Updated: 2026-11-06 Guide # Why does my Mac still charge to 100%? Usually because macOS charges to 100% now and then to keep its battery estimates accurate. Shutdowns, Optimized Charging and app conflicts come next. You set a limit, or turned on Optimized Battery Charging, and then found your MacBook sitting at 100%. It’s one of the most common battery questions, and there’s almost always a simple reason. Here are the eight we see, in the order to check them. ## 1\. macOS is checking the battery This is the one most people don’t know about. Apple says that whether you use Optimized Battery Charging or Charge Limit, **your Mac will occasionally charge to 100% to maintain accurate battery state-of-charge estimates**. The battery’s gauge needs to see a full charge now and then to keep its percentage honest. It’s normal and nothing to fix; afterwards the Mac goes back to your limit. ## 2\. Optimized Battery Charging decided you’ll need it Optimized Battery Charging isn’t a limit. It learns your routine and holds at 80% only when it predicts you’ll stay plugged in, then finishes to 100% before it expects you to unplug. If your days vary, it often charges fully. For a fixed number, use Charge Limit on macOS 26.4 or later, or a charge limiter app. ## 3\. The Mac was shut down while plugged in Apps can’t run while a Mac is off, so an app’s limit can’t hold then: a Mac left plugged in while shut down charges to 100%. Sleep instead of shutting down, or unplug before you shut down. With Chargeberry, the limit is back as soon as the Mac starts again. ## 4\. Someone chose a full charge “Charge to Full Now” in macOS’s battery menu, or Charge to 100% Now, a Full by plan or the Travel preset in Chargeberry, all charge to 100% on purpose. In Chargeberry, Charge to 100% ends two minutes after you unplug and Full by ends at its time, so the limit comes back without you doing anything. ## 5\. The app isn’t actually in control Charge limiter apps need a background helper that macOS asks you to approve once, in System Settings › General › Login Items & Extensions. If it was never approved, or was turned off, the app can show your limit without being able to hold it. Chargeberry says so in its menu and links straight to the setting. ## 6\. Two things are controlling charging Two charge limiter apps, or an app plus Optimized Battery Charging or macOS’s Charge Limit, undo each other’s work: one stops charging, the other starts it. Keep one. Chargeberry warns when it finds AlDente, BatFi, batt or Battery Toolkit installed, or Optimized Battery Charging or macOS’s Charge Limit turned on. **Moved from another app?** Remove its helper, not just the app. On macOS 27, users have reported leftover helpers from old battery apps interfering with the new limits. ## 7\. macOS changed under the app macOS 27 locked the charging controls that every limiter used, and apps that hadn’t updated stopped holding their limits, so Macs charged to 100%. A report on macos-tahoe.com lists AlDente, batt and Battery Toolkit among those affected before their updates. Update your app (AlDente 1.39, batt 0.9.0 and Chargeberry 1.1 support macOS 27). [What changed in macOS 27](https://chargeberry.app/guides/macos-27-battery-charge-limit/) ## 8\. A calibration is running A calibration, whether you started it in Chargeberry or another app, charges to 100% first on purpose, then runs the battery down. In Chargeberry the menu shows each step, such as “Calibrating, step 2 of 4: holding at 100%”, and you can stop it at any time. [How calibration works](https://chargeberry.app/guides/calibrate-macbook-battery/) > According to Chargeberry’s own tests, when the process holding a charging switch was killed, normal charging came back within 1 second. That fail-safe is deliberate: if the app or its helper ever stops, the Mac charges normally rather than not at all. — Measured by Chargeberry: Chargeberry’s crash-safety test, part of its hardware self-test, run on a MacBook Air (M1, 2020) on October 28, 2026: a client holding the charge switch, then the charger switch, was killed with kill -9 while the switches were read back from the battery controller. Last verified October 28, 2026. ## A quick checklist 1. Click the battery icon: does it say “Charging On Hold” or “Charged to \[%\] Limit”? 2. Is only one thing controlling charging (one app, Optimized Charging off)? 3. Is the app’s helper approved in Login Items & Extensions? 4. Was the Mac shut down, or did someone choose a full charge? 5. Is your app up to date for your macOS version? ## Questions about charging to 100% **Is it a problem if my Mac charges to 100% once in a while?** No. An occasional full charge is normal and doesn’t undo the benefit of a limit. What wears a battery is sitting at 100% day after day, especially while warm. macOS even does it on purpose now and then to keep its percentage accurate. **How often does macOS charge to 100% for calibration?** Apple doesn’t say how often. It says only that with Optimized Battery Charging or Charge Limit, your Mac will occasionally charge to 100% to maintain accurate battery state-of-charge estimates. **How do I see why my Mac is charging?** Click the battery icon in the menu bar: macOS shows “Charging On Hold” when Optimized Battery Charging is waiting and “Charged to \[%\] Limit” at its Charge Limit. Chargeberry’s menu says in plain words what it’s doing, for example “Held at 80% · running on the charger”. **My limit stopped working after a macOS update. Why?** macOS 27 locked the low-level charging controls that battery apps used, so older versions of those apps stopped holding their limits. Update the app; on macOS 27, Chargeberry 1.1 or later sets macOS’s own charge limit instead. **Does Chargeberry ever charge to 100% by itself?** Only when you ask: Charge to 100% Now, a Full by plan, a Travel (100%) limit, or a calibration you start. Each one ends on its own and your limit comes back. ## Sources - [Apple: About Optimized Battery Charging and Charge Limit on Mac](https://support.apple.com/en-us/102338), checked November 6, 2026 - [Battery Toolkit README (charging while shut down)](https://github.com/mhaeuser/Battery-Toolkit) - [Report: charge limit apps on macOS 27 (macos-tahoe.com)](https://macos-tahoe.com/blog/macos-27-battery-charge-limit-apps-broken-aldente-batt-charging-to-100-fix-2026/)