---
title: Lowercase processor
description: Converts a string to its lowercase equivalent. If the field is an array of strings, all members of the array will be converted. 
url: https://www.elastic.co/elastic/docs-builder/docs/3028/reference/enrich-processor/lowercase-processor
products:
  - Elasticsearch
---

# Lowercase processor
Converts a string to its lowercase equivalent. If the field is an array of strings, all members of the array will be converted.


| Name             | Required | Default | Description                                                                                                                                                                                                                    |
|------------------|----------|---------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `field`          | yes      | -       | The field to make lowercase                                                                                                                                                                                                    |
| `target_field`   | no       | `field` | The field to assign the converted value to, by default `field` is updated in-place                                                                                                                                             |
| `ignore_missing` | no       | `false` | If `true` and `field` does not exist or is `null`, the processor quietly exits without modifying the document                                                                                                                  |
| `description`    | no       | -       | Description of the processor. Useful for describing the purpose of the processor or its configuration.                                                                                                                         |
| `if`             | no       | -       | Conditionally execute the processor. See [Conditionally run a processor](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#conditionally-run-processor). |
| `ignore_failure` | no       | `false` | Ignore failures for the processor. See [Handling pipeline failures](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#handling-pipeline-failures).       |
| `on_failure`     | no       | -       | Handle failures for the processor. See [Handling pipeline failures](https://docs-v3-preview.elastic.dev/elastic/docs-builder/docs/3028/manage-data/ingest/transform-enrich/ingest-pipelines#handling-pipeline-failures).       |
| `tag`            | no       | -       | Identifier for the processor. Useful for debugging and metrics.                                                                                                                                                                |

```js
{
  "lowercase": {
    "field": "foo"
  }
}
```