yes, you will be able to format the floppies just fine for PC usage
if they are standard amiga floppies then they will be 720kb DD disks on pc

keropi wrote on Today, 18:17:

yes, you will be able to format the floppies just fine for PC usage
if they are standard amiga floppies then they will be 720kb DD disks on pc

OK thanks for that!

720kb is only half of the 1.4MB standard
DD is one sided right?
HD is bough sided?

If only half the capacity then probably not worth bothering with for my usage. but hear is a link to them anyway https://www.ebay.co.uk/itm/267763391716

PS, i remember a while ago someone hear telling me that the smaller type disks only had one whole at the top (cant remember if this is true or not though) they look like they only have the one

Yes I have a big stack of blue DD ex-Amiga disks that I use with my XT that only has a DD controller.

The_Retro_Jimmy_Club wrote on Today, 18:53:

OK thanks for that! […]
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keropi wrote on Today, 18:17:

yes, you will be able to format the floppies just fine for PC usage
if they are standard amiga floppies then they will be 720kb DD disks on pc

OK thanks for that!

720kb is only half of the 1.4MB standard
DD is one sided right?
HD is bough sided?

If only half the capacity then probably not worth bothering with for my usage. but hear is a link to them anyway https://www.ebay.co.uk/itm/267763391716

PS, i remember a while ago someone hear telling me that the smaller type disks only had one whole at the top (cant remember if this is true or not though) they look like they only have the one

there are very few 1.44mb floppies on that listing from what I can see...
as is expected for an amiga the disks are DS/DD 720kb ones ... you can easily spot them because they only have 1 square hole (HD 1.44mb floppies have 2 holes)

The_Retro_Jimmy_Club wrote on Today, 18:53:

720kb is only half of the 1.4MB standard
DD is one sided right?
HD is bough sided?

Both are double-sided.

3.5" Double Density = 9 sectors/track
3.5" High Density = 18 sectors/track

DD disks are precious for those with DD-only machines, eg. PC XT or Amiga.
PC AT (286 and above) support both DD and HD, so it's better to use HD.

The_Retro_Jimmy_Club wrote on Today, 18:53:

720kb is only half of the 1.4MB standard
DD is one sided right?
HD is bough sided?

DD is Double Density
HD is High Density

Original floppy formats were Single Density = one clock bit per one data bit (almost nobody uses SD these days and many PCs FDCs can't do SD)
Double Density encoded differently requiring 1/2 the bits.
High Density is different still and is at a higher transition rate (500kbbs .vs. 300kbps on 3.5")

5.25" was not quite the same - a 5.25" drive rotates faster at HD (making the bits spread out more) which is why HD 5.25" is only 1.2m .vs. 1.44m for 3.5

Almost nobody uses single-sided drives any more

PC DS/DD 5.25" drive is 360k = 40tracks x 2heads x 9sectors x 512 bytes= 368,640 bytes

My Altair had Shugart SA400s (one of the first 5.25" drives) SS/SD 90k = 35tracks x 1 head x 10 sectors x 256 byes = 89,600

Quite a differnce in capacity - For information on common floppy drive characteristics - I refer you to the ImageDisk documents/help screens.

I have a box of Parrot single-sided 5.25" disks that I bought out of curiosity. They format to 180K as you would expect.

Errius wrote on 43 minutes ago:

I have a box of Parrot single-sided 5.25" disks that I bought out of curiosity. They format to 180K as you would expect.

Have you tried formatting them to 360 KB ?
I suspect they would format just as well - most (or even all?) "SS" floppies actually have the magnetic coating on both sides.