MacBook Won't Turn On

Work out which problem you've

Press the power button and pay attention.

• Nothing at all. No fan, no chime, no keyboard backlight, screen completely black. This is a power problem.
• Something happens but the screen stays dark. Fans spin or you hear the startup sound. The Mac is running and you can't see it. That's a display problem.
• It starts and then stops. Apple logo appears, progress bar stalls, or it loops. The hardware is fine and the software isn't. That's a boot problem.

No power at all

1. Charge it for at least 15 minutes with a known-good cable and adapter. A deeply discharged battery shows no sign of life for several minutes after you plug it in. This alone resolves a surprising share of cases.
2. Try a different cable, adapter and outlet. USB-C cables fail more often than adapters, and charge-only cables from other devices sometimes won't do the job.
3. Check for a light. MagSafe should glow. If nothing lights up on any combination of cable and outlet, suspect the port or the adapter.
4. Force restart. Hold the power button for 10 seconds, release, then press it again normally.
5. Reset the SMC, Intel only. On non-removable-battery Intel MacBooks, shut down, hold Shift-Control-Option on the left side plus the power button for 10 seconds, release everything, then start normally. Apple silicon has no SMC to reset, and a full shutdown accomplishes the same thing.

Powers on, screen stays black

1. Turn the brightness up. Obvious, and it happens, particularly after an external display was connected.
2. Shine a torch at the screen at an angle. If you can faintly see the desktop, the panel is fine and the backlight has failed. That's a repair.
3. Disconnect every peripheral, especially external displays and docks. A confused display configuration can leave the internal panel dark.
4. Reset NVRAM, Intel only. Restart while holding Command-Option-P-R for about 20 seconds. Display and resolution settings live there.
5. Listen for signs of life. If it chimes and the fan spins but nothing appears on any display, that's a hardware fault worth an appointment.

Starts and then fails

This is the most recoverable category and the one where software fixes apply.

1. Safe Mode. On Intel, hold Shift during startup. On Apple silicon, hold the power button for startup options, then hold Shift while selecting your disk. Safe Mode loads a minimal system and skips third-party startup items. If it boots here, something you installed is the cause.
2. Check the progress bar. A bar that moves slowly and eventually finishes is usually a macOS update completing. Leave it alone, even for an hour.
3. Recovery mode. Detailed in Recovery mode explained. Run First Aid in Disk Utility against both the volume and its container.
4. Reinstall macOS from Recovery. This replaces system files without touching your data, and it fixes a corrupted system that First Aid can't.
5. Apple Diagnostics. Hold D at startup on Intel, or hold the power button then press Command-D on Apple silicon. It returns a reference code worth quoting to a technician.

The full-disk case

One cause worth calling out because it looks like a hardware failure. A startup disk with no free space can fail to boot, hang at the progress bar, or log you straight back out again. macOS needs room for swap and temporary files during startup, and a disk at 100% doesn't have it.

Boot into Safe Mode or Recovery, delete some large files, and try again. If the Mac had been warning you about storage before this happened, start here rather than at the bottom of the list.

When to stop and book a repair

Some symptoms aren't worth troubleshooting further. No response at all on multiple known-good chargers, liquid contact, a burning smell, a swollen trackpad or case, or repeated kernel panics in Safe Mode all point at hardware.

Check warranty status by serial number before paying for anything, and mention any Apple Diagnostics reference code you saw. It shortens the conversation considerably.