# `AggregationsVariableWidthHistogramAggregation` [interface-AggregationsVariableWidthHistogramAggregation]

| Name | Type | Description |
| - | - | - |
| `buckets` | [integer](./integer.md) | The target number of buckets. |
| `field` | [Field](./Field.md) | The name of the field. |
| `initial_buffer` | [integer](./integer.md) | Specifies the number of individual documents that will be stored in memory on a shard before the initial bucketing algorithm is run. Defaults to `min(10 * shard_size, 50000)`. |
| `script` | [Script](./Script.md) | [ScriptSource](./ScriptSource.md) |   |
| `shard_size` | [integer](./integer.md) | The number of buckets that the coordinating node will request from each shard. Defaults to `buckets * 50`. |