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Understanding the following terms in the context of Google BigQuery Storage can help you make informed decisions about managing your data and optimizing storage costs:

#1 Storage Units.

The storage units are used to measure the amount of data that can be stored on a device or storage media. 

Storage units can be defined as decimal units of measurement or binary units of measurement.

Decimal units are based on the decimal system, which uses base 10. 


The following are the most common decimal storage units:

  1. Bit (b) is a binary digit, meaning it can be either a 0 or a 1. It is the smallest unit of data storage. 
  2. Byte (B) is a group of 8 bits. One byte can represent a single character or a small piece of data.
  3. Kilobyte (KB) is equal to 1,000 bytes.
  4. Megabyte (MB) is equal to 1,000 kilobytes.
  5. Gigabyte (GB) is equal to 1,000 megabytes.
  6. Terabyte (TB) is equal to 1,000 gigabytes.
  7. Petabyte (PB) is equal to 1,000 terabytes.

Binary units are based on the binary system, which uses base 2. 


The following are the most common binary storage units:

  1. Kibibyte (KiB): A kibibyte is equal to 1,024 bytes.
  2. Mebibyte (MiB): A mebibyte is equal to 1,024 kibibytes.
  3. Gibibyte (GiB): A gibibyte is equal to 1,024 mebibytes.
  4. Tebibyte (TiB): A tebibyte is equal to 1,024 tebibytes.
  5. Pebibyte (PiB): A pebibyte is equal to 1,024 tebibytes.

To summarize:

1 KB (kilobyte) = 1,000 bytes (decimal) 

1 KiB (kibibyte) = 1,024 bytes (binary)

This means that a KiB is about 2.4% larger than a KB.


What is the purpose of using decimal and binary storage units?

The main difference between decimal and binary storage units is that binary storage units are more precise. 

Therefore, they are better suited for estimating the monthly cost of data storage and processing.

That’s why when you use the Google Cloud pricing calculator, all the storage units are defined using binary units of measurement:


The decimal storage units are most commonly used for displaying storage information to end users. 

For example, the storage information displayed for a BigQuery data table uses the decimal storage units:

#2 Number of rows.

In Google BigQuery, when you view the details of a data table, it shows the number of rows under the storage information: