How to Clone a Hard Drive. If you need to migrate your data or are… | by PCMag | PC Magazine - Medium

If you need to migrate your data or are looking to keep a backup handy, you can clone your hard drive. Here's how to do it in Windows and on a Mac.

By Whitson Gordon

There are plenty of great services that can back up your files, but sometimes you need something a bit more bulletproof. Maybe you're migrating your Windows installation to a new drive, or perhaps you want a complete one-to-one copy in case anything goes wrong. In those cases, your best bet is to clone your hard drive, creating an exact copy you can swap in and boot up right away.

Some backup services, like IDrive and Acronis, have built-in disk-cloning features, supplementing to the normal file backup. We'll be using some free tools designed specifically for drive cloning in this guide, though. If you want a true backup solution with supplemental cloning features, check out one of the paid options. But for one-off clones (like if you're migrating your OS to a new drive), these tools will be all you need.

For this process, you'll obviously need two drives: the source drive (with the data you want to clone), and the destination drive (where you're cloning that data to). If you have a desktop computer and both drives are installed internally (or you're just cloning to a USB external drive for backup), great! You're ready to continue.

If, however, you're using a laptop with only one drive bay, you'll need an external SATA-to-USB adapter, dock, or enclosure to connect your bare drive to the computer. Once you've connected your drive, you can go through the cloning process, then disconnect it and install the drive internally.

In most cases, your destination drive will probably need to be as large as, or larger than, your source drive. If it isn't, you'll need to free up space on your source drive and shrink the main partition down to fit. (You'll probably only need to do this if you're migrating from a hard drive to a smaller SSD; we have a separate guide on that process here.)

Windows users have lots of great cloning tools available, but we'll be using Macrium Reflect Free. It's free, easy to use, and widely loved by many, so it's hard to go wrong.

To install Macrium Reflect, download the Home Use installer and start it up. It's just a tiny tool that will download the actual installer for you, based on the type of license you want. Choose the temporary folder for these files — I just put them in my Downloads folder — and click the Download button.

Once it's finished, it'll automatically launch the Macrium installation wizard, which you can click right on through — the default options should be fine for our purposes. You can safely delete all the installer files from your Downloads folder once the wizard has finished.

Open Macrium Reflect and you'll see a detailed list of the disks connected to your computer. You have two main options: you can directly clone one disk to another, or create an image of a disk. Cloning allows you to boot from the second disk, which is great for migrating from one drive to another. Imaging, on the other hand, allows you to store as many full, one-to-one copies of your source disk as the destination's space will allow, which is useful for backups.

Select the disk you want to copy (making sure to check the leftmost box if your disk has multiple partitions) and click "Clone This Disk" or "Image This Disk."

In the next window, choose your destination disk — the one that will house your newly copied data. Note that this will erase all data on the disk, so be careful which one you choose. If there's any old data on it, you may want to select it and click the "Delete Existing Partitions" button until the drive is empty.

If you're cloning to a larger drive, you'll want to click the "Cloned Partition Properties" button at the bottom of this window, and extend your main partition to fill up the entire space of the disk.

The next page will ask if you want to schedule this clone, which is useful if you want to regularly image your drive for backup purposes. I've skipped this, since I'm just doing a one-time clone. On the page after that, you can also save the backup and its schedule as an XML file for safe keeping, but I've unchecked that option for the same reason — I'm only doing this once for now.

Finally, Macrium Reflect will begin the cloning process. This can take some time depending on the size of your drive, so give it time to do its thing. If you cloned your drive, you should be able to boot from it now by selecting it in your BIOS. If you're imaging your drive, you can actually keep the second drive connected for future image backups.

If you're on a Mac, we recommend SuperDuper for all your cloning needs. It's free, simple to use, and has been around for years. Download the app, open the DMG file, and double-click on the icon to install. (Don't drag it to your /Applications folder like you would most Mac apps; double-clicking on it should install it to your computer.)

Once installed, open SuperDuper and you'll be greeted with its incredibly simple, intuitive interface. In the first menu next to "Copy," select the source disk you want to clone. In the second menu, select the destination disk you're cloning to — this will fully erase the drive in that second menu, so make sure there isn't anything important on it! When you're ready, click the "Copy Now" button. The process will begin. (Yeah, it's that easy.)

This may take a while, but when it's done, you have two choices. If you want to replace your Mac's internal drive with the new drive (say, if you're migrating to a larger drive), you can open up your Mac and swap those now, then boot up as normal.

If you want to boot your cloned drive from USB, you can hold the Option key as your Mac starts up and select it from the boot list. Your cloned drive will be in the exact state your computer was during the cloning process, and you can continue working without skipping a beat.