Reformat SD card after using it in Raspberry Pi

If you try to use your SD card after having used in your Raspberry Pi, you will notice your OS will not recognize it. OS X and Windows, it's pretty straight forward to reformat, but Linux is a bit more tricky, but here are the steps.

1. Mount the SD card
2. Find where the SD card is mounted. You can do this with the

   mount

   command. If you are not root, try

   sudo mount

   The SD card will be mounted to something like

   /dev/sdbx

   where x is a number.
3. Delete the partitions from the SD card. The command to do this is

   sudo fdisk /dev/sdbx

   • p is the command to list the existing partitions
   • d is the command to delete the partition
   • delete all partitions on SD card
4. Create a new partition
   • n is the command to create a new partition
   • p is the command to to create a primary partition
   • Enter the sector size 8192
   • press Enter to select the default last sector
   • t is the command to change the partition type
   • We want FAT32, so type b
   • w is the command to write the changes to disk
5. Now we have our partition created, we need to format it. We can do that using this command

   mkdosfs -vF 32 /dev/sdb1

6. That is it. You should now see this drive as a thumb drive again.