My macbook’s hdd is 512 gb.
Only 110 GB is used now.
I plugged a apfs formatted 256 gb usb flash disk and I got this error
“A disk larger than 998,77 GB is recommended for backing up this Mac.”
I won’t do periodical backups.
One time only.
If I need another and newer backup I'll format the USB Flash drive and have another one time backup.
Is this alright to backup into this usb flash drive?
MacBook Pro 14″
Ideally, you want an external disk that is 2-2.5x the capacity of your internal storage. If you have 512 GB internal storage, you should be looking at a 1 TB external drive.
Note that you don't have to follow the recommendation. I have multiple TM backups, but one of them is my 2 TB internal drive backing up to an external 2 TB SSD, i.e. the same size as internal storage.
In your case, with 110 GB used you should be able to back up to a 256 GB drive. You state that you see an error, but is it? An error will prevent you from running the backup at all. Probably what you're seeing is a warning – ignore it and run the backup anyway.
Ideally, you want an external disk that is 2-2.5x the capacity of your internal storage. If you have 512 GB internal storage, you should be looking at a 1 TB external drive.
Note that you don't have to follow the recommendation. I have multiple TM backups, but one of them is my 2 TB internal drive backing up to an external 2 TB SSD, i.e. the same size as internal storage.
In your case, with 110 GB used you should be able to back up to a 256 GB drive. You state that you see an error, but is it? An error will prevent you from running the backup at all. Probably what you're seeing is a warning – ignore it and run the backup anyway.
Recommended External HDD Size For One Time Time Machine Backup
