How to Use Min and Max Aggregation in Elasticsearch

In Elasticsearch, use the min and max aggregations inside an aggs clause to find the smallest and largest values of a numeric field. These aggregations return the minimum or maximum value found in the documents matching your query.

Syntax

The min and max aggregations are used inside the aggs section of a search request. You specify the field to aggregate on. The structure looks like this:

• aggs: The aggregation container.
• min or max: The aggregation type.
• field: The numeric field to find the minimum or maximum value.

json

{
  "aggs": {
    "min_value": {
      "min": {
        "field": "your_numeric_field"
      }
    },
    "max_value": {
      "max": {
        "field": "your_numeric_field"
      }
    }
  }
}

Example

This example shows how to find the minimum and maximum price from a list of products indexed in Elasticsearch.

json

{
  "size": 0,
  "aggs": {
    "min_price": {
      "min": {
        "field": "price"
      }
    },
    "max_price": {
      "max": {
        "field": "price"
      }
    }
  }
}

Output

{
  "aggregations": {
    "min_price": {
      "value": 5.99
    },
    "max_price": {
      "value": 199.99
    }
  }
}

Common Pitfalls

Common mistakes when using min and max aggregations include:

• Using a non-numeric field, which causes the aggregation to fail.
• Not setting size to 0 when you only want aggregation results, which returns unnecessary hits.
• Misnaming the aggregation keys, which can cause confusion when reading results.

json

{
  "size": 10,  
  "aggs": {
    "max_price": {
      "max": {
        "field": "price"
      }
    }
  }
}

// Better:
{
  "size": 0,
  "aggs": {
    "max_price": {
      "max": {
        "field": "price"
      }
    }
  }
}

Quick Reference

Aggregation	Purpose	Field Type	Notes
min	Finds the smallest value	Numeric	Use inside aggs; returns single value
max	Finds the largest value	Numeric	Use inside aggs; returns single value

Key Takeaways

Use min and max aggregations inside aggs to find smallest and largest numeric values.

Always set size to 0 if you only want aggregation results to avoid unnecessary data.

Ensure the field used is numeric; otherwise, the aggregation will fail.

Aggregation results are returned under the keys you define in the aggs section.