# How to 'empty' a big index?

**URL:** <https://discuss.elastic.co/t/how-to-empty-a-big-index/382586>\
**Category:** Elasticsearch\
**Created:** [October 10, 2025, 12:30pm UTC](https://discuss.elastic.co/t/how-to-empty-a-big-index/382586 "2025-10-10T12:30:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![smm](https://avatars.discourse-cdn.com/v4/letter/s/bb73d2/32.png) [@smm](https://discuss.elastic.co/u/smm)\
**Post date:** [October 10, 2025, 12:30pm UTC](https://discuss.elastic.co/t/how-to-empty-a-big-index/382586/1 "2025-10-10T12:30:00Z")

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Hi there,

I am in the situation to have a regular index (not a time-series index & not a data stream).  
This index got really big - about 13GB. Because of its nature I cannot use ILM.

What can I do instead to have an empty index so to say?  
The data in it is of no interest.

It is one primary and no replica.

Any hint would helps - thanks!

Cheers!

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<div class="post-metadata">

**Author:** ![stephenb](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stephenb/32/40856_2.png) [@stephenb](https://discuss.elastic.co/u/stephenb)\
**Post date:** [October 10, 2025, 2:09pm UTC](https://discuss.elastic.co/t/how-to-empty-a-big-index/382586/2 "2025-10-10T14:09:52Z")

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Hi @smm

> [@smm](#):
>
> What can I do instead to have an empty index so to say?  
> The data in it is of no interest.

What exactly do you mean "empty" the index... If you do not want any of the data you can just delete the entire data... I suspect that is not what you want

You can use [delete\_by\_query](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-delete-by-query) to clean out documents. This will delete the documents that match the query BE CAREFUL.

Elastic marks these documents as deleted, and eventually, they will be "expunged" by merging in the background

To speed this up, you can run a force merge with expunge deletes to clean up the deleted documents

> **[Force a merge
 | Elasticsearch API documentation](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-indices-forcemerge)**
>
> All methods and paths for this operation:
> POST
> /\_forcemerge
> 
> 
> POST
> /{index}/\_forcemerge
> Perform the force...

with

> `only_expunge_deletes` boolean `true`  
> Specify whether the operation should only expunge deleted documents