List.Split
ListSplits a list into a list of sub-lists, each of a specified maximum size.
Syntax
List.Split(list as list, pageSize as number) as listParameters
| Name | Type | Required | Description |
|---|---|---|---|
list | list | Yes | The source list to split. |
pageSize | number | Yes | The maximum number of items in each sub-list (chunk size). |
Return Value
list — A list of lists, where each inner list contains at most pageSize items.
Remarks
List.Split divides a list into consecutive chunks (sub-lists), each containing at most pageSize items. If the list length is not evenly divisible by pageSize, the last chunk contains the remaining items and will be smaller than pageSize. The result is always a list of lists — never a flat list.
This function is the standard way to implement batching in Power Query. Common use cases include splitting a large list of IDs to send in multiple API requests, chunking a dataset for incremental processing, or paginating through records. After splitting, use List.Transform or List.Accumulate to process each batch.
The pageSize must be a positive integer; using 0 or a negative number causes an error. If the source list is empty, the result is an empty list. To flatten a list of lists back into a single list, use List.Combine.
Examples
Example 1: Split into chunks of 3
List.Split({1, 2, 3, 4, 5, 6, 7, 8, 9}, 3)Result | |
|---|---|
| 1 | {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}} |
Example 2: Last chunk may be smaller
List.Split({1, 2, 3, 4, 5}, 2)Result | |
|---|---|
| 1 | {{1, 2}, {3, 4}, {5}} |
Example 3: Process a list in batches of 100
let
AllIDs = List.Numbers(1, 250),
Batches = List.Split(AllIDs, 100),
BatchCount = List.Count(Batches)
in
BatchCountThe final output — the scalar count 3, representing the number of batches produced.
Result | |
|---|---|
| 1 | 3 |