How to Format a Hard Drive

Guide Note How to Format a Hard Drive gives you a few simple steps on how to clean off your drive and start anew.

Table of Contents

Formatting a Hard Drive Tips

Technology How Tos

Formatting a hard drive is a basic task in working with computers and something everyone who does more than type on a keyboard should know how to do. Formatting a hard drive is not complicated, but it should be done with caution because there's the potential of losing a lot of data if you're not careful.

(Creative Commons photo by Sarah)
Determine exactly what you want to do with your hard drive. Do you want to reinstall Windows? Do you want to just clean up your drive?¹ Do you want to remove any sensitive data?² There are a couple of different ways to format a hard drive, and your particular needs will determine the best way to proceed. Often reinstalling Windows can fix stability problems you get from frequently changing hardware and installing and uninstaling programs.
If you're simply re-installing Windows and want to start fresh, Windows will give you an opportunity to do this while you run through the setup program. Often reinstalling Windows can fix stability problems you get from frequently changing hardware, installing and uninstaling programs. ³
If you want to format a new hard drive, install a non-Windows operating system or just leave the hard drive blank, then you need to follow the steps for formatting from DOS.⁴
If you are trying to remove sensitive data, you need to be aware that simply formatting will leave data visible to those who have the desire and the tools to look at your data.⁵ If this is the case, you will want to do all that you can to wipe your old data before formatting.

If you are formatting a hard drive with data on it, make sure you have a backup or copy of everything on that hard drive just to be safe.⁶

Look at all of the programs that are installed on your computer.
1. Make sure you have a copy of the program to reinstall and have its serial number written down.
2. Make sure you backup any data files associated with the program.
Backup all of your documents such as Word or Excel documents.
Don't forget to save your bookmarks and emails.
You can manually backup your data by copying all of the files you know you need or you can use a backup software program. There is one that comes with Windows XP that you can use. This article details how to install and use that program. ⁷

If you plan to just re-install an operating system than it's probably a good idea just to go ahead with the standard formatting (skip to the instructions below for reinstalling windows) without any other additional methods for deleting data.
However, if you are giving away, selling, trading or otherwise disposing of the hard drive, you should probably make sure your data can't be recovered. This is good to prevent any kind of identity theft or just keep your information private from anyone else who might read it. Follow these steps for wiping your data.⁸
1. Decide the level of security you need. You can either buy software or hire a company to wipe your old data. Wiping is done by overwriting your entire hard drive with either a 0 or a 1.
2. Find a reputable company and buy the software or their services.
3. Use the software to completely over-write your drive one or more times.
4. Now you are ready to format the drive.

Go into your BIOS and set the boot priority to start with your CD-ROM drive.
1. To do this restart your computer and watch the screen for the instructions on which key to hit during the start-up process to enter the BIOS.⁹ It is often the Delete or F8 key.
2. Hit the appropriate key and look through the menus for a boot priority option.
3. When you find the boot priority option, change it to boot from the CD first, this is often done by using the arrow keys or pageup and pagedown keys.
Restart your computer with the Windows (Win98 & higher) disc in the drive.
Follow the steps to boot from the CD.
You can choose to install a fresh copy of Windows or refresh Windows but this will not give you the option to format.¹⁰
Using the commands given delete the current partition.¹¹
Select the now un-partitioned space and create a new partition.¹²
Choose that partition and format it choosing a file system (Fat or NTFS)
Continue installing Windows.

Make, create or download the files to make a boot disk. Bootdisk.com is a good resource.¹³
Go into your BIOS and set the floppy disk as the first boot device. ⁹
Restart your computer with the boot disk in the drive.
Choose to boot your computer using CD ROM support.
Type the following command "fdisk."¹⁴
Select "Y" to enable large disk support
Use this program to create a partition and set the partition to active.
When formatting is done reboot with the boot disk again.
Type in the following command "Format c:" where c is the letter of your hard drive
Type "y" to accept.
You are now done formatting the drive.