When (and how) to use computed fields

When (and how) to use computed fields

Computed fields can give you instant insight into your data—from performing calculations to looking up information across tables. Teams use computed fields to save time on otherwise-manual processes, and to protect their workflows from human error.

You can use computed fields to crunch numbers, look up who edited a record, or build a button to run a script. In this article, you’ll explore different computed fields and how you can make the most of them in Airtable. 

What are computed fields?

Computed fields are a set of field types that automatically update based on conditions you set—allowing you to easily reference the latest information from linked records, create custom calculations, and more. They’re computed within a specific field in your table automatically, rather than directly edited by a collaborator.

Explore computed fields

There are different kinds of computed fields in Airtable, which have different uses depending on your needs. 

If you want to keep track of important changes across your base, you can use the computed fields for created by, created time, last modified by, and last modified time.

To analyze information with linked records, you can surface key details across tables with lookup; aggregate data and build formulas with rollup; or simply add the number of linked records together with count. 

Finally, buttons allow you and your team to perform actions with a single, customizable click.

Let's explore different computed fields, and how you can use them in your workflow:

1. Keep track of important changes

Computed fields can be used to keep track of the whos, whats, and whens of a record being changed, creating a paper trail for future reference.

There are four computed fields that can be used to track these kinds of changes in your base: 

If you want to know, for example, which records were most recently added, you could sort by Created time. Need more context about a certain record? Check out your Created by field to see who entered it. 

If you’re working in a team, you might need to know who last updated a piece of information with Last modified by, and when it happened with Last modified time.

2. Aggregate data using linked records

Linked records ​​create a relationship between records in different tables, and give you access to a special set of computed fields that perform calculations. 

For example, if you’re organizing a publication, you might have a table containing key data about each article, and another table containing key data about each of your writers. With linked records, you can understand which articles are assigned to specific writers on your team, connecting these two critical lists of information.

With computed fields, you can perform calculations with those linked records. You might want to count the number of records that meet certain criteria, lookup information tied to specific records in another table, or rollup trends with a formula.

You can use these computed fields to keep track of your team’s workload, see how many tasks have been assigned to each person, or calculate how much overtime they’ve worked. 

Let’s explore the different uses for different calculations, in order of complexity: 

Summarize the number of linked records with Count

A count field simply counts the number of records in a linked record field. 

Once you configure a count field, you can quickly see the number of assignments each writer has for an at-a-glance summary of their workloads. As articles are assigned, reallocated, and completed, the count record will automatically keep track of the total.

Surface relevant details across tables with Lookup

A lookup field allows you to pull linked record data from one table into another. 

For example, if you’re planning production in the Articles table and want to quickly understand which of your writers are located in a certain city, you can use a lookup to surface those details. 

Anytime you assign a writer to a project, their work location will automatically populate in the lookup field. And you can do the same with any piece of information you have about your writers, as long as it’s recorded in the Writers table.

Aggregate insights with Rollup

A rollup field allows you to perform calculations, create aggregates, and build formulas from specific cells in linked records. 

You can use it to calculate the total cost for an article, or the average cost of an article amongst your entire editorial database.

Take action: Add a count field

If you’re linking records across tables, you can use the count field to add them up—let’s say, for example, you want to know how many articles each writer has been assigned or produced. Because you’ve linked your Writers table to your Articles table, you could use the count field to calculate it.

3. Take action with button

A button field is an interactive field type that lets you trigger certain actions directly from your Airtable base.