What are calculated fields in Looker Studio

Calculated fields: your next step for advanced reports

Once you're comfortable building basic reports in Looker Studio, you’ll probably run into new needs—like showing percentages, combining metrics from different platforms, or tagging content based on performance.

That’s where calculated fields come in. They’re super useful when you need more customized or advanced social media reports.

Still getting started with Looker Studio? You might want to check out this guide first: Getting started with your reports in Looker Studio

What’s a calculated field?

A calculated field is a new field you create inside Looker Studio using a formula. That formula uses the data you already have, and lets you transform it, combine it, or display it differently—depending on what you want to show in the report.

For example, you might create a field that tags posts by performance level, or one that shows the total follower count across multiple networks.

In short: calculated fields help you build custom metrics without changing your original data source.

This ensures calculations run properly and avoids unexpected results in charts.

Where do you create them?

You can create calculated fields in two places:

• In the data source: This makes the field reusable across different charts and reports.

• In a specific chart: This limits the field to just that one visual.

Both options work—what matters is how and where you plan to use the field.

Things to keep in mind

• Use aggregations correctly
  When combining metrics, make sure to wrap them with aggregation functions like SUM(), AVG(), or COUNT(). Otherwise, Looker Studio might throw errors or give you wrong results.

Example: SUM(Facebook Evolution > Reels Published) + SUM(Instagram Evolution > Reels)

This ensures calculations run properly and avoids unexpected results in charts.

• Check your chart’s level of detail
  The output of a calculated field can vary a lot depending on how your chart is set up—by day, by campaign, by social network, etc.
  Think about whether your formula makes sense at the row level, total level, or by date. Sometimes it helps to test things out in a simple table first to make sure you're getting what you expect.

• Don’t mix dimensions and metrics without care
  Dimensions (like dates or campaign names) behave differently from metrics (like clicks or impressions). If you try to combine them in a formula without understanding how they work, Looker Studio might reject it—or worse, show misleading results.

• Test your formulas in simple tables
  Before adding a formula to a complex chart, it’s a good idea to test it out in a basic table with just a few filters. It’ll help you spot issues early and better understand what’s going on behind the scenes.

• Not all functions work the same everywhere
  Some functions—like REGEXP_MATCH or CASE—can behave differently depending on whether you use them in the data source or directly in a chart. If a formula isn’t working, try moving it to the other context and see what happens.

⚠️ Looker Studio won’t always flag logic errors
Sometimes Looker Studio will accept a formula that technically works, but gives you the wrong numbers because the logic isn’t right. For example, averaging percentages across rows might not make sense depending on your data. Always double-check what you’re really calculating.