Wasabi uses base-2 (sometimes also referred to as base-1024) rather than base-10 (sometimes also referred to base-1000) in all billing-related usage measurements, billing dashboard displays, and billing invoices. This means that:
1 GB = 1,073,741,824 bytes (1024 bytes * 1024 * 1024)
1 TB = 1024 * 1 GB = 1,099,511,627,776 bytes
1 PB = 1024 * 1 TB = 1,125,899,906,842,620 bytes
Although the IEC indicates that the use of base-2 calculations should result in the use of terms like GiB, TiB, and PiB (rather than GB, TB, and PB), Wasabi follows the AWS convention of using the GB, TB, and PB terms even when using base-2 calculations (many other vendors in the storage industry do the same).
Below is some more fun reading on this topic: