Why does my MacBook keep turning off on its own?

First work out what turned off

A dark display, a locked session, sleep and an unexpected shutdown can look alike until you try waking the Mac. Note what happens next: do the open apps return immediately, or does the computer go through startup again? Does macOS show a message that it restarted because of a problem?

Don't assign a cause from one symptom alone. A battery percentage shown before the event isn't a diagnostic measurement of the battery's ability to supply power, and warmth doesn't establish that a particular shutdown was thermal.

Back up and record the pattern

When the Mac is stable enough, back up important work before repeated tests. Save open documents often while investigating. A shutdown that interrupts a write can leave that work incomplete even if macOS later starts normally.

Keep a short record of the circumstances: connected to power or unplugged, approximate battery level, app and task, accessories, and any message after startup. Record whether it happens at a particular time or after a repeatable action. These details help distinguish a scheduled event from a random failure.

Don't copy a stranger's panic-log interpretation onto your machine. If macOS reports that it restarted because of a problem, our unexpected-restart guide owns that investigation and explains the report's limits.

If it turns off only on battery

Open System Settings › Battery › Battery Health on macOS 15 Sequoia, macOS 26 Tahoe or macOS 27 Golden Gate. Read Apple's reported condition and Maximum Capacity. The battery-health guide explains where cycle count lives and why the numbers describe different things.

If the condition is Service Recommended, Apple says the battery holds less charge than new or isn't functioning normally. It can still be usable, but repeated loss of power is a symptom worth reporting for service rather than dismissing because the laptop works while plugged in.

Also establish that it was genuinely charging. A Mac can run from an adapter while battery charging is paused, or a low-powered setup may struggle with the current workload. See the not-charging guide for status messages and adapter wattage for the model's recommendation.

If removing power reliably triggers an immediate shutdown, preserve the evidence and arrange evaluation. Repeatedly draining it to zero or attempting a calibration ritual isn't a substitute for checking the battery and power system. A capacity percentage alone can't identify which component needs repair.

If it restarts with a message or during one app

Apple's unexpected-restart instructions start with checking software and connected devices. Install available supported app updates, then check macOS through System Settings › General › Software Update. Back up before making a major operating-system change.

If one app repeatedly triggers the event, save its version, the task and the file type. Check the developer's current macOS and Apple silicon support, including plug-ins. If macOS specifically identifies an app as a possible cause, follow its recommendation and contact that developer.

Safe mode can help test software loaded at startup. If a fault disappears there, return to a normal startup and investigate the optional software; don't assume that simply living in safe mode is the permanent solution.

A non-erasing reinstall is a later option in Apple's troubleshooting path. It doesn't repair every hardware fault and won't necessarily remove a bad third-party component it retains. Use the reinstall guide only after the smaller checks and a backup.

Test accessories one at a time

Shut down and disconnect optional peripherals such as hubs, external drives, printers and mobile devices. Keep direct compatible power connected if needed. Use the Mac for roughly the circumstances in which the fault normally occurs.

If the problem stops, reconnect one item at a time and retest. Include its cable in the investigation. A dock providing power, a storage device used by an app and a loose connector are different roles; note which one you changed.

If the fault persists with optional devices removed, use Apple Diagnostics. Apple explicitly recommends this in its unexpected-restart checklist. Record any reference code for service; a test that cannot complete is not the same as a successful result.

Heat, sleep and scheduled behaviour

For a hot laptop, move to a firm, ventilated surface and pause demanding optional work. Apple's ambient operating range is 10–35 °C (50–95 °F); don't confuse room temperature with a CPU threshold. If unusual heat persists during light work, investigate the workload and get help rather than repeatedly reproducing an abrupt shutdown.

Read the heat guide for the full checks. It isn't possible to prove a thermal shutdown just from a warm enclosure after the fact.

If the session wakes immediately, review display and sleep behaviour instead of battery replacement. On current macOS, System Settings › Lock Screen includes display-off timing, while Battery settings cover related power options. Change a setting only after identifying the behaviour you want to alter.

If a full shutdown happens at the same clock time, ask whether someone configured a power schedule or whether the Mac is managed. Apple's scheduling documentation describes this feature. On a work Mac, ask IT before changing a schedule or management setting.

When to arrange service

Get help if the Mac cannot stay running long enough to back up, turns off immediately when unplugged, repeatedly fails diagnostics, or still shuts down after the software and accessory checks. If it now won't start, use the no-power procedure.

Provide the pattern, error messages, diagnostic code and backup situation. An app's health estimate is useful context but not a repair authorization or a guarantee that the battery is the cause. For battery-only pricing, use the replacement-cost guide.

How Tend helps

Tend's free Battery page shows health, cycles and charging state, while app CPU, memory and estimated watts help describe the workload. Pro's heat warning and daily health record can add context when the Mac is running; no app can diagnose every sudden power loss or monitor a Mac that is off.

Questions

Related guides

Sources

Sources checked 23 October 2026. These are documented steps and specifications; no repair, installation or performance test was run for this guide.

• Apple, If your Mac restarted because of a problem
• Apple, If you see battery Service Recommended
• Apple, Use Apple Diagnostics to test your Mac
• Apple, Keep your Mac laptop within acceptable operating temperatures
• Apple, Schedule your Mac to turn on or off
• Apple, Reset the SMC of your Mac

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