# MacBook battery guides

> Plain answers to common MacBook battery questions: charge limits, 100% charges, macOS 27, calibration, health and keeping a Mac plugged in.

URL: https://chargeberry.app/guides/
Author: Ayesha Gagan (https://chargeberry.app/about/)
Published: 2026-11-06 · Updated: 2026-11-06

Guides

# MacBook battery guides

Plain answers to common MacBook battery questions: charge limits, 100% charges, macOS 27, calibration, health and keeping a Mac plugged in.

Every guide here is written by the maker of Chargeberry and checked against Apple’s own support pages and the battery tests Chargeberry runs on a real MacBook. Where macOS can do something by itself for free, the guide says so first.

[**How to limit MacBook charging to 80%** Three ways: macOS’s Charge Limit, Optimized Battery Charging and an app, with steps for each.](https://chargeberry.app/guides/limit-macbook-charging-to-80/) [**How to set a Mac charge limit below 80%** 60% or 50% for a desk Mac: which apps can on macOS 14–26 and on macOS 27.](https://chargeberry.app/guides/mac-charge-limit-below-80/) [**Why does my Mac still charge to 100%?** The eight usual reasons, from macOS’s own calibration charges to two apps fighting.](https://chargeberry.app/guides/why-does-my-mac-charge-to-100/) [**macOS 27 and charge limits** Why battery apps stopped working on macOS 27, which work now, and what they can no longer do.](https://chargeberry.app/guides/macos-27-battery-charge-limit/) [**How to calibrate a MacBook battery** What calibration does and doesn’t do, a manual method, and one-click calibration.](https://chargeberry.app/guides/calibrate-macbook-battery/) [**Is it bad to keep a MacBook plugged in?** What really wears a battery out, and five habits that keep it healthy for years.](https://chargeberry.app/guides/keep-macbook-plugged-in/) [ **MacBook battery health calculator** Work out health, wear per cycle and how far the battery is from Apple’s 80% mark.](https://chargeberry.app/battery-health-calculator/)

> According to Chargeberry’s charge-rate record, charging from 0 to 79% took about 1.2 minutes per percent, 80 to 89% about 2.5 minutes, and 90 to 99% about 3.0 minutes. On that Mac the last 20% takes nearly as long as the first 50%, so stopping at 80% skips the slowest part of every charge.

— Measured by Chargeberry: Chargeberry’s own charge-rate record on a MacBook Air (M1, 2020) with a 30 W USB-C charger: 104 one-percent steps, as recorded on October 28, 2026. A different Mac or charger changes the times.