# Convert a 1.44MB Floppy to 720K

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## Introduction: Convert a 1.44MB Floppy to 720K

In this Instructable I will tell you how to covert a 1.44MB floppy disk to 720K format (MB = Megabytes, K = Kilobytes).

You might be wondering: "Why in the world would I want to convert a high capacity disk into a disk only capable of half it's original size?!?". Well, what if you have an old computer that only excepts 720K disks? Since 1.44MB disks are much more common than 720K, why not convert a few of your extras? This is something I figured out on my own, but I'm sure it's been done before.

Ok, now that we're done with the intro, let's make these!

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## Step 1: What You'll Need...

You will need:

At least one 1.44MB floppy you would like to convert, (make sure there is no data you want to keep!)

Tape

That's all!

Now we can make the disks!

## Step 2: Make the Disks!

Ok, now we make them!

Find the square hole that does not have a slider. (Circled in the above pictures). Take a short length of tape, (3-4cm or 1 1/2inchs long), and cover both sides of the hole.

The reason this works, is that there is no physical difference between 1.44MB floppy disks and 720K disks, except that the 720K disk is missing the hole that you just covered.

## Step 3: Format the Disks!

Now we need to format the disk.

You will need a computer with a floppy drive.

1: Insert your newly converted floppy into the drive.

For Windows Users: Go to my computer, right-click on the A: drive, click Format.

For Dos users, at the command prompt, type "Format A:".

Note: If your computer has two floppy drives, make sure you replace all the "A:"s in this step with whatever drive you put the disk in.

## Step 4: You're Done!

Ok, you're done!

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## 28 Discussions

I have experienced that converting an HD (1.44MB) to a DD (720K PC/800K Mac) disk this way it may cause problems when the disk is used and already formatted in the HD format.
The original HD layout will not be properly erased, instead only the DD format will be recorded over the HD format causing an unusable disk.
The solution would be a demagnetizer. You could use either a bulk tape eraser or a tape head demagnetizer (I use the latter, works perfectly).
Just move the demagnetizer around on the plastic case of the disk (doesn't harm when the demagnetizer is touching the case) in a circle motion for a minute, then move the demagnetizer away from the disk to about 3-4 ft.

Afterwards format it and it will work reliably!

Also: some floppy drives use an optical sensor for determining the disk type, so black electrical tape may be necessary in some cases.

Good to know! I don't have any more computers that use floppy disks, but perhaps the info you've posted will be useful for others. Maybe this is why I had so many headaches with floppy reliability back when I was playing around with the old laptops!

There is a good chance somebody will find that useful. Many older Macintoshes use 800/400K disks that are an absolute unobtainum today. And it doesn't even matter if you use an HD or a DD disk. Everything that isn't unformatted or has already been used won't work.
Macs take floppies a bit more seriously than PCs seem to do. After every format they check the format. When just applying tape and formating HD at 800K, it won't even check the first sector successfully and immediately eject the floppy saying "This disk is bad."
After demagnetizing, all the same disks that failed that test before now check fine in both my IIci and my beige G3.
That's how I know that this method works.

ps :make sure you put spaces between the A: and the /T and the 80 and the /N

Hah, ok. It worked great for me on all the computers I tried it on. Hopefully it's working for you!

in addition to my last discussion, make sure you put black marks over the taped holes in case your floppy has a light sensor, also FORMAT A: command did not work , the DOS window in XP worked with Format A: /T:80 /N:9 havent tried this command in the win 7 dos window

Thanks for this info, I have tons of 1.44s, but all my old keyboards like my Korg X-3, only take 720s, the price they want for old 720s is ridiculous. You da man

Glad it was helpful! Have fun with those old keyboards; anything with a floppy drive as the main storage has got to be interesting...

Dear I have tried on Pentium D System with 1.44MB Floppy drive but have problem in format with 720k.

There could be a few things going wrong, but first of all, you'll need to make sure you've reformatted the disk to the 720K format. It's also possible that your Dell's floppy drive doesn't support 720K floppy disks, but that's highly unlikely. I would (First of all) make sure the tape is still level with the surface of the disk (not indented or pressed in), then format it. If all else fails, it could be your disk is bad, so try again with another floppy disk.

Thanks! This worked perfectly, managed to save files on an old Smith Corona word processor I got, and then my old Dell read the floppy fine, and that has internet. I can now upload fines created on a word processor! :D

If I recall correctly, bytes are abbreviated by a capital B, whereas the lowercase one is for bits. Also mega is a capital M, therefore your sizes should be MB and KB accordingly (capital K, because binary value kilo prefix is like that).

Not being an ass or anything and I wouldn't have commented about this at all, but since the instructable is computer related I just had to.

That's fine, no offense taken. I'll edit the instructable to fix that!

one problem, no one uses floppy disks any more

Not exactly, If you are trying to write files to use an old Apple 2C There are quite a few hobbyists that use older tech. Take the Amiga fanatics for example.

I agree, I'm sure there are many hobbyists that use old tech, including me.

I love old tech someone has to curate the museum pieces for the next generations.