Freeware Utility

Hope this is the right place to ask:

Is there a Bootable freeware utility that can partition adjust etc the   HDD  without having

to boot the computer.      Or  to prepare a  new  hdd for use?

I ask because I have always found tinkering withh hdd with the os and other methods

rather painful.

Not sure what you mean by "without having to boot the computer". That "bootable freeware utility" has to sit on some piece of hardware somewhere whether it be a flash drive, or a DVD or another hard drive. And to work the computer (meaning the motherboard, RAM, CPU) has to "boot" in order to "see" that other drive. So the "computer" has to boot regardless. Now if the computer boots to that flashdrive or to the DVD drive or secondary drive before it touches the normal primary/boot hard drive, then the computer still boots, it just does not boot into the normal operating system (typically Windows).
 
My favorite partition utility is  EASEUS Partition Master Free. This program is free for home, non-commercial use. If you install this new drive as a secondary drive (not the boot drive), it is very easy to use. But note this program will even let you partition the boot drive, resize partitions on the boot drive, or remove partitions on the boot drive too - without losing any data. That makes it a very powerful program.

I've used it 100s of times over the years and have never had it fail. HOWEVER, messing with partitions always comes with risks. A power glitch in the middle of modifying the partitions, for example, could cause major corruption. So when doing anything with partitions with any program, always make sure you have a good backup of your data first.

You did not say what OS you have but if Windows 10, note it's own Disk Management feature is much easier to use than previous Windows versions.

One more thing - new hard drives always come already formatted and ready to use straight from the factory.

Thank you very much.

I meant utility to be on dvd or usb stick to be used without having to boot the O.S.

Something like the old  Kill Disk that one used to erase aprtition or entire hdd.

Reason,  to erase one OS to install another without the new os erasing the old one.

I will install  Easeus . I am sure it will come in handy.

Reason,  to erase one OS to install another without the new os erasing the old one.

You would not need to "erase" the old. During the install, if you follow the prompts carefully when installing the new OS, you should be given the option to format (and partition) the drive. Formatting the drive will effectively "erase" the old OS.

That said, Easeus should still do what you want.

Thank you. Already installed  Easeus.

No problem. Don't forget backups.