Where does Elasticsearch store its data?

If you run the Windows MSI installer (at least for 5.5.x), the default location for data files is:

C:\ProgramData\Elastic\Elasticsearch\data

The config and logs directories are siblings of data.

Have a look into the Nodes Stats and try

http://127.0.0.1:9200/_nodes/stats/fs?pretty

On Windows 10 with ElasticSearch 7 it shows:

"path" : "C:\\ProgramData\\Elastic\\Elasticsearch\\data\\nodes\\0"

According to the documentation the data is stored in a folder called "data" in the elastic search root directory.

If you've installed ES on Linux, the default data folder is in /var/lib/elasticsearch (CentOS) or /var/lib/elasticsearch/data (Ubuntu)

If you're on Windows or if you've simply extracted ES from the ZIP/TGZ file, then you should have a data sub-folder in the extraction folder.