Whats the difference between a quick/non quick format?

[OnionRings]

I noticed in the disk management tool when making a new volume for my HDD it said quick format or not, I unchecked it out of curiosity and its SOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO SLOW. What's the difference between a quick and non quick, obviously besides the speed, what's it doing?

[Mamonos]

To make it short if you select one of the non-quick options, it's writing random data across al the disk (one or multiple times depending on the option you chose) in order to make your past data unretrievable. If you select quick format it just erases the content of the drive but other people may be able to retrieve the data.

 

If you are the owner of the drive or there is no sensitive data on it then quick format is perfectly fine.

If you are planning to sell the drive I would go for a longer, deeper format.

 

[OnionRings]

1 minute ago, Mamonos said:

To make it short if you select one of the non-quick options, it's writing random data across al the disk (one or multiple times depending on the option you chose) in order to make your past data unretrievable. If you select quick format it just erases the content of the drive but other people may be able to retrieve the data.

 

If you are the owner of the drive or there is no sensitive data on it then quick format is perfectly fine.

If you are planning to sell the drive I would go for a longer, deeper format.

 

Thank you. I'm just gonna let it finish, I didn't plan on selling it but its already going now and I don't want to risk disturbing it and ruining the drive. I need somewhere to store my MASSIVE 150GB games yknow?

 

Edit : Oh, there's a cancel format button in DM... is it safe? I imagine so, since its there.

[RadiatingLight]

7 minutes ago, OnionRings said:

Thank you. I'm just gonna let it finish, I didn't plan on selling it but its already going now and I don't want to risk disturbing it and ruining the drive. I need somewhere to store my MASSIVE 150GB games yknow?

 

Edit : Oh, there's a cancel format button in DM... is it safe? I imagine so, since its there.

yeah just cancel you'll be fine.

 

ELI5 explanation is that quick format erases the "table of contents" of the hard drive, marking everything as empty space. The 1s and 0s for all your files are still there on the drive, but since there's no table of contents, they're hard to get to and will get overwritten (since the area is marked empty) when you write other data to the drive.

not-quick format actually goes and erases all of the bits to all of the data. This takes way longer, but it means the files are well and truly gone. (ish, there are always ways to get them back and if you really want government-secret level security there are programs that write all 0s, then all 1s, like 20 times in a row to truly expunge all data, but this is good enough for most things.)

[OnionRings]

Quick format, more like instant transmission format.

 

I cancelled and the quick one literally worked right away. O_o

[Master Disaster]

54 minutes ago, Mamonos said:

To make it short if you select one of the non-quick options, it's writing random data across al the disk (one or multiple times depending on the option you chose) in order to make your past data unretrievable. If you select quick format it just erases the content of the drive but other people may be able to retrieve the data.

 

If you are the owner of the drive or there is no sensitive data on it then quick format is perfectly fine.

If you are planning to sell the drive I would go for a longer, deeper format.

 

Not entirely accurate.

 

When you do a quick format it erases the partition table so the drive has no record of where anything is stored, it does not delete the data at all and free software can recover the partition table and restore the drive including all files & foiders.

 

When you do a full format it deletes the partition table and it zeros out each track on the platter however even this is not enough to remove the data entirely and its still pretty easy to recover drives that have been full formatted. Heck you can usually recover data from 2 full formats assuming it hasn't been overwritten.

 

It you want the drive to be unrecoverable then it MUST BE secure erased which involves a full format then filling the drive with garbage data then another full format (this can be repeated multiple times with each pass making the data harder to recover). The idea is that if a recovery is attempted all they get is the garbage data.

 

IIRC the military standard is 5 passes before a drive is considered fully unrecoverable though its worth noting, only real experts could get anything after a few formats. Your average home software won't stand a chance.

[Gamer Schnitzel]

Just to add to this, a quick format does not actually "delete" the data. Basically what the computer does is tell the drive how much space is available on it. A harddrive actually only starts deleting files when it becomes full and it does not actually delete it. Harddrives cannot be deleted and do not know how to delete themselves either.

They can only write over the existing data. This means that when you do a quick format nothing is deleted. The computer simply tells the drive to set the available storage shown in Windows to maximum. The stuff is still gonna be on there but the drive will tag it as "not needed" and "okay to be overwritten when nearing full capacity"