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Multi-currency reporting in Looker Studio powered by official exchange rates.

Use Official Exchange Rates in Looker Studio

In the previous post, we shared how to import official exchange rates from the Global Exchange Rates API into Google Sheets using Apps Script.

Now let’s take it a step further: connect the exchange rates to your business data inside Looker Studio (formerly Google Data Studio) and perform automated currency conversion.

Looker Studio is Google’s free business intelligence tool that lets you connect data from various sources — like Google Sheets, BigQuery, or external APIs — and turn it into interactive dashboards and reports. It’s commonly used for financial reporting, marketing analytics, and internal KPIs.

First of all, we will need a Google Sheet with:

  • A sheet with your transaction data, including currency codes (e.g., USD, GBP).
  • A sheet named Exchange Rates (from the previous post).

1. Connect Google Sheets to Looker Studio

  • Go to Looker Studio and create a Blank Report.
  • Click Add data → Choose Google Sheets.
  • Select your spreadsheet and add both sheets (transactions and exchange rates).
  • Name each data source clearly (e.g., Sales, Rates).

2. Combine the Two Tables

You need to join the exchange rates to your transaction data using the currency code.

  • In Looker Studio, go to Resource → Manage blends.
  • Click Add a Blend.
  • Choose Sales as the left table, and Rates as the right table.
  • Join the two using the Currency column:

Sales.Currency = Rates.Currency

Click Save and Add to Report.

3. Add a Calculated Field for EUR Conversion

In your report, select the blended data source.

  • Add a new metric using Create Field.
  • Name the field: Amount in EUR.
  • Formula: Amount / Rate against EUR.

This converts the original transaction into your base currency (EUR), using the official rate. You can wrap the formula with ROUND() if needed for presentation.

4. Build Your Dashboard

With everything connected, you can now visualize your consolidated data.

If you need historical rates by date, you can use the /historical endpoint.

Conclusions

With just a Google Sheet and a few Looker Studio steps, we now have a multi-currency reporting setup powered by official central bank rates.

This approach works well for small to medium datasets. For larger datasets, consider connecting the API directly to BigQuery or a proper ETL pipeline.

If you don’t have an API key yet, you can get one on the get-started page, with official rates from 80+ central banks and tax authorities.