# Calculator The Calculator step provides you with predefined functions that you can execute on input field values. This Calculator step is an easy and quick alternative to custom JavaScript commonly used for calculations. To use, specify the input fields and type of function to perform and return results. You can also specify a field to remove from the result (output) after all values are calculated, which is useful for removing temporary values. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.pentaho.com/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/calculator.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.