A calculated column uses fields from the same record or a related parent record to calculate a value in real time.
Example: First Name + Last Name = Full Name.
A rollup column calculates an aggregate value from related child records, such as SUM, COUNT, MIN, MAX, or AVG.
Example: Totaling all Opportunity values for an Account.
| Calculated Column | Rollup Column | |
| Data source | Same record or related parent record | Related child records |
| Calculation | Calculated in real time | Calculated asynchronously |
| Purpose | Calculates a value | Aggregates related records |
| Functions | Math, text, conditions, etc. | SUM, COUNT, MIN, MAX, AVG |
| Example | Quantity × Price = Total | Total Opportunity value for an Account |
Interview tip: Remember Calculated = current record; Rollup = related records.
