---
title: ES|QL TO_BOOLEAN function
description: 
url: https://www.elastic.co/docs/reference/query-languages/esql/functions-operators/type-conversion-functions/to_boolean
products:
  - Elasticsearch
---

# ES|QL TO_BOOLEAN function
## Syntax

![Embedded](https://www.elastic.co/docs/reference/query-languages/esql/images/functions/to_boolean.svg)


## Parameters

<definitions>
  <definition term="field">
    Input value. The input can be a single- or multi-valued column or an expression.
  </definition>
</definitions>


## Description

Converts an input value to a boolean value. A string value of `true` will be case-insensitive converted to the Boolean `true`. For anything else, including the empty string, the function will return `false`. The numerical value of `0` will be converted to `false`, anything else will be converted to `true`.

## Supported types


| field         | result  |
|---------------|---------|
| boolean       | boolean |
| double        | boolean |
| integer       | boolean |
| keyword       | boolean |
| long          | boolean |
| text          | boolean |
| unsigned_long | boolean |


## Example

```esql
ROW str = ["true", "TRuE", "false", "", "yes", "1"]
| EVAL bool = TO_BOOLEAN(str)
```


| str:keyword                               | bool:boolean                             |
|-------------------------------------------|------------------------------------------|
| ["true", "TRuE", "false", "", "yes", "1"] | [true, true, false, false, false, false] |