General Introduction

As more image files are created, there will be more and more data and files stored in your associated backup destination. In order to ensure data integrity and make full use of your available storage space, it is important to back up changed data regularly.

Once you have created a backup task, you will see this task listed in the Backup Management window. Hover your mouse pointer over this task, select the 3 lines icon and then click "Backup". You will see three options: Full Backup, Incremental Backup, and Differential Backup. The following paragraphs describe the differences among them and can help you select which backup scheme you want to use:

Home Incremental Differential

If you would like to configure a scheduled differential or incremental backup, you can simply check the steps to create a schedule backup. In the schedule "Advanced" settings, you can configure the differential, incremental or full backup as the scheduled backup type. As a result, the backup will run a scheduled differential or incremental backup.

Tips: For detailed info about how to perform an Incremental or Differential backup, please refer to How to Do Incremental and Differential Backup.

What's the Difference between Full Backup, Incremental and Differential Backup?

Full Backup

A full back up takes a snapshot of all the data on the selected folders, partitions or hard disks at the time the backup is performed and saves it to an image file. A full backup is always the basis of any incremental and differential backup. A Full Backup can be used to restore all the files and folders from its image to the state when the image was created. Once you have performed a Full backup, you can create Incremental and Differential backups. These are much quicker to create than a Full backup of the same data and the images created are smaller.

Incremental Backup

An Incremental backup takes a snapshot only of the changed and newly added files based on the previous related backup, either a full or incremental backup depending on what was last done. Data that have not changed will not be backed up. Thus, the time and image storage space required for incremental backups are both less than a full backup. A Full Backup must exist as the start point of a series of incremental backups. A typical set would be in time sequence. All the image files in an incremental backup series share a sequential relationship and data can be recovered to the state when any Incremental Backup was done. If any one of the incremental image files in the sequence is damaged or missing, then subsequent image files will be invalid.

Differential Backup

A Differential Backup is always directly related to its originating Full Backup. It will back up all data added and changed since the Full backup was done. Therefore, compared to a full backup, the backup time and image file storage space required are both less. If one of the differential backup image files becomes damaged or lost, it will not affect others. All data can be returned to the state when the Differential Backup was done. If there are a lot of changes made to the data between backups, then each Differential Backup will become progressively larger, because each one will contain more changes made since the last Full Backup was done. Compared to Incremental back up, Differential Backup costs more time and requires more disk space but is more robust in terms of being able to restore when preceeding differential backups are damaged or missing.

Differences among Full, Differential and Incremental Backup

The differences mainly lie in the backup source, backup time, image storage, and restore speed. Here is a table listing these items.

Differences Between Three Backup Types

Which to Choose, Full, Differential or Incremental?

With the descriptions above, you might have found out that the method of "Full Backup + Incremental Backup" or "Full Backup + Differential Backup" would be more convenient than a single full backup. Therefore, after performing a full backup, you can choose whether to use an incremental or differential backup to deal with the changed and newly added data and files. What's more, the use of "Full Backup +Incremental Backup" has been employed more frequently than other approaches as it only deals with the changed files since the last incremental backup. Therefore, if you need to back up data regularly, this method will be more efficient. The "Full Backup + Differential Backup" method is also a good solution, however, compared to the incremental backup option, it requires more time and storage space but is more resilient to loss of a differential backup file in a series.


  • If anyone of the incremental image files in the sequence is damaged or missing, the subsequent image files will be invalid.

  • A Full Backup must exist as the start point of a series of incremental backups or differential backups.

  • If you have not created any backup task and you want to create an incremental backup or a differential backup, then you need to create a new backup task first and Aomei Backupper will run it as a full backup by default at the first time.