## What is a formula?

Plecto formulas are logical expressions similar to those in Excel or Google Sheets. They calculate your data, such as the value of sales, the number of calls, month-to-date targets, and more.

On their own, formulas are not limited by specific time periods. The time period becomes relevant only when a formula is added to a widget.

All formulas are created in a **formula editor**. You can open the formula editor in **Formulas** **>** **+ New formula** or from widgets on dashboards and reports.

**Default date**

When calculating your data, formulas look at your data source's default date field. Say you created 5 registrations today but updated 20 – the default date helps Plecto understand which number to show.

## What is a KPI?

In Plecto, a Key Performance Indicator or KPI is a combination of **formula + widget + time period**.

Unlike formulas, KPIs __are__ bound to specific time periods.

For example, say you have a formula that counts the number of calls from a data source. You can use this formula to see the KPI for today, another KPI for the current month, a third one this month filtered by teams or employees, and so on.