After installing a 1 TB hard drive, why might the OS report less unformatted capacity than expected?

When you install a new hard drive, the capacity reported by the operating system may indeed be less than the expected unformatted capacity. The option regarding old data previously stored on the drive does not address the typical behavior seen when a new drive is installed. In most cases, a brand-new drive should not have any old data, and thus this would not be a valid reason for a discrepancy in reported capacity.

Instead, one of the primary reasons for the reported capacity being less than expected relates to how storage capacities are calculated. Storage manufacturers often define 1 TB (terabyte) as 1,000,000,000,000 bytes based on decimal (base 10) calculations. However, operating systems typically use binary (base 2) calculations, where 1 TB is considered to be 1,099,511,627,776 bytes (which translates to 1,024 gigabytes).

As a result, when you format a new hard drive, the operating system interprets the total space using base 2 calculations, leading to a noticeable difference in reported capacity compared to the manufacturer’s specifications. This is why understanding the difference between base-10 and base-2 calculations is important when assessing storage space.

Therefore, the reason for