Backing up HDD to restore it on another SSD I want to switch out my current HDD for a SSD in my Mac. However I don't want to reinstall the OS and all my software. 

How can I backup (image) the entire HDD to restore it later as image with Disk Utility on another SSD? Accordingly, if I have 50GB partition for my current system, will that partition size somehow sustain through the image to the new SSD and make the other space that would be available on a larger harddrive then unusable? If so, how can I avoid this behavior?
Three ideas. First addresses your idea about Disk Utility. The next on the method I have used. The third is an idea to just do a switch of the disks &amp; use an external enclosure.


You can use Disk Utility, but I’ve actually had better luck not
using it or any official Apple tools. With Disk Utility you would
simply make an image of your boot disk to another drive then boot up
your machine from some other device—a CD, DVD, USB, etc…—or even the
recovery partition. Once booted you go to Disk Utility &amp; restore.
But like I said, I have had better luck with other methods.
I have done clones &amp; migrations over the years using tools such as
SuperDuper!
or Carbon Copy Cloner. Just hook up an
external drive with an empty partition as big—or bigger—than the
source, clone the disk as a bootable copy to the new disk. Install
the new drive in your machine, but then boot up from the copy you
just made &amp; clone it in reverse from the external drive to the
internal. Maybe Time Machine can do this, but I don’t use that for backups.
But I have a third solution I think would work well. Get an external
enclosure for the drive you are going to remove, place the drive in
that enclosure, place the new drive in your machine, boot from the
external drive &amp; then clone it in reverse from the external drive to
the internal.


The last one has a slight risk since if you have no backup &amp; you remove your internal drive &amp; somehow damage it in the process, well… You have nothing. I recommend method 2 since it’s a tried &amp; true way of imaging a machine. Works great!