How long it Takes to Encrypt 4TB Empty Hard Drive with BitLocker?

Don't worry too much, it’s normal to take so long when you choose "Encrypt Entire Drive". According to official data, BitLocker encryption time can take about 1 minute per 500 MB encrypted. Hence, for your 4TB USB hard drive, it may take days or longer. The BitLocker time to encrypt relates to your computer’s processing power, disk speed, and the type of encryption you chosen.

Microsoft BitLocker provides two encryption options. The encryption time for these two options differs significantly. The concrete differences between the two options are as below:

1. Encrypt Used Disk Space Only

This option only encrypts existing files on the disk and is suitable for new drives. For a new hard drive, it only contains necessary data files for the file system, which are usually only megabytes in size. Therefore, using this option for BitLocker drive encryption is very fast, can be completed in seconds.

Besides, the system will automatically encrypt the written data when you write new data to encrypted disk, ensuring data security to the greatest extent.

However, it should be noted that if you hard drive has been used for a while, choosing this option may leave residual data which are not completely deleted at the risk of being recovered. You can delete files from USB flash drive permanently before enable BitLocker.

2. Encrypt Entire Drive

Encrypted entire drive, one time encryption, is more secure compared to encrypting only the used space. It’s used for encrypting every available space on your USB drive to make sure that any previously deleted or formatted data cannot be recovered by others.

In this option, BitLocker encrypts the entire disk, both data and free space. So, when you use BitLocker encryption, you may notice that the free space on your disk is gone, and after completing the BitLocker encryption, the available free space automatically restored.

Note: When using full disk encryption, you can choose to pause or postpone the encryption process. No need to worry about computer shutdowns during encryption with BitLocker, because the process will resume from where it left off.

Conclusion

If it is a "brand new blank hard drive" or there are no deleted important data on the drive just like yours, you can choose to encrypt only the data portion, which takes minimal time.

If it is an old drive, for security reasons, it is recommended to encrypt all available space (including blank space). Although it may take a long time, with the previously deleted files being irrecoverable, your valuable data is under BitLocker powerful safeguard.

You can also choose iSunshare BitLocker Genius for Windows as your assistant to encrypt your external hard drive. It’s more convenient and faster than system utilities.

Tips: iSunshare BitLocker Genius for Windows helps us better handle the BitLocker through straightforward graphical user interface.