When you use BigQuery BI Engine, your charges are based on the BI Engine capacity you purchased for your project. There are two ways to purchase BI Engine capacity:


BI Engine stores BigQuery metadata and table data in memory. The amount of data stored is constrained by the amount of capacity you purchase. When you run a query that retrieves results from data that is stored in BI Engine, you are not charged for reading the data.

If you run a query that produces query results larger than the size of your BI Engine capacity, the BI Engine self-tuning feature uses BigQuery slots to run the query. When BigQuery slots are used to run a query, you are charged based on BigQuery on-demand query pricing for the query job. When slots are used to run a query, all BigQuery quotas and limits on query jobs apply.

Free tier

BI Engine offers up to 1 GB of free capacity to Google Data Studio users. This free tier is available to all Data Studio users, without needing a reservation. This free capacity is intended for testing purposes only and should not be used to run production workloads. There are no SLO guarantees around this free tier. For production workloads, purchase BI Engine capacity as described in the next section.

On-demand capacity pricing

BI Engine on-demand capacity pricing is as follows:

Flat-rate capacity pricing

BigQuery offers flat-rate pricing for high-volume or enterprise customers who prefer a stable monthly cost for queries rather than paying the on-demand price per GB of data processed. If you enroll in BigQuery flat-rate pricing, the cost of your BI Engine capacity is bundled in the monthly flat-rate price. For more information about BigQuery flat-rate pricing, see the BigQuery Pricing page.

For every 500 flat-rate slots that you purchase, you will also receive 25 GB of bundled BI Engine data-processing capacity, up to a maximum of 100 GB of free capacity with a purchase of 2,000 slots. The following table shows how much capacity you receive at each level:

Number of slots Bundled BI Engine capacity (GB)
500 25
1000 50
1500 75
2000 100

If all of your Google Cloud projects combined need a total of more than 100 GB of data-processing capacity, you can purchase more at the on-demand rate. If your projects also use separate billing accounts, each account is billed an amount proportional to how much capacity its projects use.

In the following example, this company has purchased 2,000 flat-rate slots, earning them 100 GB of bundled capacity. However, their projects together require 120 GB of capacity; therefore, the remaining 20 GB must be purchased at the on-demand rate. Each account is billed for a fraction of the additional 20 GB, based on how much of the total it needs.

In this example, the Sales account is billed for 5 GB of on-demand capacity. We find this figure by dividing the additional capacity (20 GB) by the total amount (120 GB), then multiplying by the total capacity needed by the project (30 GB).

Cloud project Billing account Capacity needed Additional billing
Project A Sales 30 GB 5 GB
Project B Finance 40 GB 6.67 GB
Project C HR 20 GB 3.33 GB
Project D HR 30 GB 5 GB
Total: 120 GB Total: 20 GB