---
title: unit
description: This setting must be one of seconds, minutes, hours, days, weeks, months, or years. The values seconds and minutes are not allowed with the period filtertype...
url: https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_unit
products:
  - Elasticsearch
  - Elasticsearch Curator
---

# unit
<note>
  This setting is used with the [age](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/filtertype_age) filtertype, with the [period](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/filtertype_period) filtertype, or with the [space](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/filtertype_space) filtertype if [use_age](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_use_age) is set to `True`.
</note>

```yaml
 - filtertype: age
   source: creation_date
   direction: older
   unit: days
   unit_count: 3
```

This setting must be one of `seconds`, `minutes`, `hours`, `days`, `weeks`, `months`, or `years`. The values `seconds` and `minutes` are not allowed with the [period](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/filtertype_period) filtertype and will result in an error condition if used there.
For the [age](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/filtertype_age) filtertype, or when [use_age](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_use_age) is set to `True`, unit, [unit_count](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_unit_count), and optionally, [epoch](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_epoch), are used by Curator to establish the moment in time point of reference with this formula:
```sh
point_of_reference = epoch - ((number of seconds in unit) * unit_count)
```

`units` are calculated as follows:

| Unit      | Seconds    | Note                                  |
|-----------|------------|---------------------------------------|
| `seconds` | `1`        | One second                            |
| `minutes` | `60`       | Calculated as 60 seconds              |
| `hours`   | `3600`     | Calculated as 60 minutes (60*60)      |
| `days`    | `86400`    | Calculated as 24 hours (24*60*60)     |
| `weeks`   | `604800`   | Calculated as 7 days (7*24*60*60)     |
| `months`  | `2592000`  | Calculated as 30 days (30*24*60*60)   |
| `years`   | `31536000` | Calculated as 365 days (365*24*60*60) |

If [epoch](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_epoch) is unset, the current time is used. It is possible to set a point of reference in the future by using a negative value for [unit_count](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/fe_unit_count).
This setting must be set by the user or an exception will be raised, and execution will halt.
<tip>
  See the [age filter documentation](https://www.elastic.co/elastic/docs-builder/docs/4836/reference/elasticsearch/curator/filtertype_age) for more information about time calculation.
</tip>