Lithium-ion batteries age fastest when held at a high charge in heat. If your MacBook lives on a charger, capping the charge is the single most effective thing you can do for its long-term health.
The “80% rule,” briefly
Keeping the battery roughly between 20% and 80% — and cool — minimizes stress. You don’t need to obsess; the big win is simply not parking at 100% all day, every day.
The built-in Charge Limit (macOS Tahoe 26.4+)
On an Apple-silicon Mac running macOS Tahoe 26.4 or later, macOS now has a real, user-set Charge Limit. Go to System Settings → Battery, click the ⓘ next to Charging, and set a limit between 80% and 100%. Your Mac then stops charging at that level while plugged in, topping up to 100% occasionally so its charge estimate stays accurate. This is the simplest way to cap charging and needs no extra app.
Optimized Battery Charging (adaptive)
Separately, macOS has long included Optimized Battery Charging. It learns your routine, holds around 80%, and finishes to 100% shortly before you normally unplug. It’s adaptive rather than a fixed cap — if you sometimes see “Not Charging” while plugged in, either this or a Charge Limit is often why.
On older macOS or Intel Macs
If you’re not on Tahoe 26.4+ (or you have an Intel Mac), there’s no built-in fixed cap — only the adaptive Optimized Battery Charging. A third-party charge-limiting app can hold the battery at a level you choose, and some add discharge and scheduling the built-in limit doesn’t.
Where Mac 4 Breakfast fits
Mac 4 Breakfast doesn’t replace the native Charge Limit — it makes the whole picture visible around it: a Smart Alert can drop from the notch the moment you hit your target so you can unplug (handy if you’d rather not leave a cap on), plus full health, temperature and cycle-count tracking so you can actually see the payoff over time — no kernel extensions or background daemons.