> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://help.sigmacomputing.com/docs/type-functions/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://help.sigmacomputing.com/_mcp/server.

# Type functions

> Browse Sigma type functions available in workbook formulas and calculations.

Type functions perform type casting or type conversion operations that transform values from one [data type](/docs/data-types-and-formats) to another.

| Function                 | Description                                                                                                                     |
| ------------------------ | ------------------------------------------------------------------------------------------------------------------------------- |
| [Date](/docs/date)       | Converts text or number values to the [date data type](/docs/data-types-and-formats#date) in [ISO](/docs/date) datetime format. |
| [JSON](/docs/json)       | Converts values to the [variant data type](/docs/data-types-and-formats#variant) in JSON format.                                |
| [Logical](/docs/logical) | Converts values to the [logical data type](/docs/data-types-and-formats#logical) in boolean format (`true` or `false`).         |
| [Number](/docs/number)   | Converts values to the [number data type](/docs/data-types-and-formats#number).                                                 |
| [Text](/docs/text)       | Converts values to the [text data type](/docs/data-types-and-formats#text).                                                     |
| [Variant](/docs/variant) | Converts text values to the [variant data type](/docs/data-types-and-formats#variant).                                          |

The following [geography function](/docs/geography-functions) also transform values from one data type to another:

|                              |                                                                                                       |
| :--------------------------- | :---------------------------------------------------------------------------------------------------- |
| [Geography](/docs/geography) | Converts GeoJSON or WKT formats to the [geography data type](/docs/data-types-and-formats#geography). |

> Official documentation and guidance for using Sigma to build AI apps, dashboards, and agents on governed warehouse data.

## Docs

- [Date](https://help.sigmacomputing.com/docs/date.md): Use the Sigma Date function to convert a text or number value to the date data type in ISO date time format.
- [Json](https://help.sigmacomputing.com/docs/json.md): Use the Sigma Json function to convert a value to JSON (or GeoJSON when converting geography data).
- [Logical](https://help.sigmacomputing.com/docs/logical.md): Use the Sigma Logical function to convert the input value into a Boolean type, with a logical value of either True or False.
- [Number](https://help.sigmacomputing.com/docs/number.md): Use the Sigma Number function to convert the input value into a number type.
- [Text](https://help.sigmacomputing.com/docs/text.md): Use the Sigma Text function to convert values to text strings (or WKT format when converting geography data).
- [Variant](https://help.sigmacomputing.com/docs/variant.md): Use the Sigma Variant function to convert the input value to the variant data type.