How to use Disk Utility to repair a Mac’s disk

What is Disk Utility on Mac?

The Disk Utility on Mac is a helpful tool that finds and repairs disk errors on Mac computers. Using the Disk Utility on Mac is often suggested when the user is experiencing unusual problems such as the Mac not being able to boot properly.

Accessing the Disk Utility on Mac?

Under normal circumstances, you should be the Disk Utility tool from the Applications folder of your Mac. However, if you are experiencing problems with getting your Mac to start normally and load into the interface of its OS, then you will have to access this utility from Recovery Mode. Here is how to do this:

1. First, you need to determine whether your Mac has an Intel processor or an Apple Silicon one. To do this, select the Apple Menu, then click on About this Mac, and look at the information shown in the window that appears on your screen. If you see an entry labeled “Chip” with the chip model written next to it, this means your Mac is with an Apple Silicon processing unit. If, instead of “Chip”, there’s a “Processor” entry followed by the name of the processor, then this means that the computer is equipped with an Intel CPU.
2. Depending on the type of processor your Mac has, do either one of the following:
   • For Apple Silicon processors, with the computer turned off, press and hold the power button – keep holding it until your Mac starts and a screen with different Startup options shows up, then release the button.
   • For Macs with Intel processors, turn on the computer and then immediately press and hold down the following keys from your keyboard: Command ⌘ + R. Keep holding the keys until the Apple logo (or another image) gets displayed on your screen.
3. If you are asked to pick a user account, select one with Admin privileges with a password that you know.
4. Next, highlight the Disk Utility option from the Utilities screen and then select Continue.

Using the Disk Utility to repair your Mac’s startup disk

1. First, you will have to select the small “view” icon located in the top-left from the central panel of the Disk utility screen and click on Show All Devices (if such an option is available).
2. Now, in the left panel, you should see the startup disk of your Mac listed at the top – expand it, then expand its container (if it has one), and select the last volume of that disk/container.
3. Click on the First Aid icon  and then click on Run/Repair Disk.
4. If the First Aid icon is grayed-out, skip this volume, and repair the next one (go from last to first).
5. Wait for the repairing process to complete and then select the next volume and repair it. After the volumes are repaired, move to the container and lastly repair the startup disk. Always go from bottom to top.

What to do if the disk you are trying to repair doesn’t show up in the Disk Utility on Mac

If you cannot see the disk you want to repair of your Mac in the left panel of the Disk Utility interface, then turn off the computer, disconnect all peripheral devices and try again. If you are using the Disk Utility to repair an external drive, you should obviously not disconnect that but make sure that it is securely connected to the computer. 

In case even after that the disk still you are trying to repair is still not show in the Disk Utility, you may need to bring your Mac to a licensed technician who can have a look at it as there might be a more serious problem with the machine that may require professional help.