Formula versus stored field types
Key Takeaway
Use a formula field when Salesforce should calculate a value, and use a stored field type when users must enter or edit it. You can't switch between the two by changing the field type.
A formula field works out its value automatically, much like a spreadsheet cell that adds up other columns. Stored field types hold values that users enter. Your choice decides whether users can edit the value, whether old records need backfilling, and whether you can change the field type later.
When to use a stored field type
Formula fields are read-only on record detail pages, so users can't type a value into them. When users must enter or edit a value themselves, use a stored field type. Examples include:
- Text, which takes up to 255 characters
- Number, which takes any number and removes leading zeros
- Date
- Checkbox, which records true or false
- Picklist, which lets users pick one value from a list you define