opensearch-docs-cn/_query-dsl/aggregations/bucket/date-histogram.md

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---
layout: default
title: Date histogram
parent: Bucket aggregations
grand_parent: Aggregations
nav_order: 20
---
# Date histogram aggregations
The `date_histogram` aggregation uses [date math]({{site.url}}{{site.baseurl}}/opensearch/supported-field-types/date/#date-math) to generate histograms for time-series data.
For example, you can find how many hits your website gets per month:
```json
GET opensearch_dashboards_sample_data_logs/_search
{
"size": 0,
"aggs": {
"logs_per_month": {
"date_histogram": {
"field": "@timestamp",
"interval": "month"
}
}
}
}
```
{% include copy-curl.html %}
#### Example response
```json
...
"aggregations" : {
"logs_per_month" : {
"buckets" : [
{
"key_as_string" : "2020-10-01T00:00:00.000Z",
"key" : 1601510400000,
"doc_count" : 1635
},
{
"key_as_string" : "2020-11-01T00:00:00.000Z",
"key" : 1604188800000,
"doc_count" : 6844
},
{
"key_as_string" : "2020-12-01T00:00:00.000Z",
"key" : 1606780800000,
"doc_count" : 5595
}
]
}
}
}
```
The response has three months worth of logs. If you graph these values, you can see the peak and valleys of the request traffic to your website month over month.