react-window is a component library that helps render large lists of data quickly and without the performance problems that often go along with rendering a lot of data. It's used in a lot of places, from React DevTools to the Replay browser.

Support

If you like this project there are several ways to support it:

• Become a GitHub sponsor
• Become an Open Collective sponsor
• or buy me a coffee

The following wonderful companies and individuals have sponsored react-window:

Installation

Begin by installing the library from NPM:

npm install react-window

TypeScript types

TypeScript definitions are included within the published dist folder

FAQs

Frequently asked questions can be found here.

Documentation

Documentation for this project is available at react-window.vercel.app.

List

Renders data with many rows.

Required props

Name	Description
rowComponent	React component responsible for rendering a row. This component will receive an index and style prop by default. Additionally it will receive prop values passed to rowProps. ℹ️ The prop types for this component are exported as RowComponentProps
rowCount	Number of items to be rendered in the list.
rowHeight	Row height; the following formats are supported: number of pixels (number) percentage of the list's current height (string) function that returns the row height (in pixels) given an index and rowProps dynamic row height cache returned by the useDynamicRowHeight hook ℹ️ Percentage heights can't be resolved during server rendering unless a defaultHeight (or a pixel height via the style prop) is specified. ⚠️ Dynamic row heights are not as efficient as predetermined sizes. It's recommended to provide your own height values if they can be determined ahead of time.
rowProps	Additional props to be passed to the row-rendering component. List will automatically re-render rows when values in this object change. ⚠️ This object must not contain ariaAttributes, index, or style props.

Optional props

Name	Description
className	CSS class name.
style	Optional CSS properties. The list of rows will fill the height defined by this style.
children	Additional content to be rendered within the list (above rows). This property can be used to render things like overlays or tooltips.
defaultHeight	Default height of list (in pixels) for initial render, before its actual height has been measured. ℹ️ Lists can't be measured during server rendering, so this value determines how many rows are server rendered. It's recommended to set this to the expected height of the list (or to specify a pixel height via the style prop).
defaultScrollOffset	Initial scroll offset (in pixels) of the list. This value is only applied once, when the list first mounts with at least one row. ℹ️ Server-rendered HTML can't be pre-scrolled, so server rendering always starts at the first row; the default scroll offset is applied once the list hydrates. ⚠️ If the list can't be scrolled that far when the offset is applied (e.g. it is hidden with display: none, or uses percentage row heights before its height has been measured), the offset is clamped or ignored and not retried. Specify a defaultHeight (or a pixel height via the style prop) when using percentage row heights.
listRef	Ref used to interact with this component's imperative API. This API has imperative methods for scrolling and a getter for the outermost DOM element. ℹ️ The useListRef and useListCallbackRef hooks are exported for convenience in TypeScript projects.
onResize	Callback notified when the List's outermost HTMLElement resizes. This may be used to (re)scroll a row into view.
onRowsRendered	Callback notified when the range of visible rows changes.
overscanCount	How many additional rows to render outside of the visible area. This can reduce visual flickering near the edges of a list when scrolling.
rowKey	Lists use the row index as a key by default. This prop can provide a custom key value. ℹ️ Custom keys can ensure better UX for sortable or filterable lists, particularly if your row components are stateful. Refer to the React documentation for more info. ⚠️ This prop cannot be auto-memoized because it is called during render. It is important to always useCallback for this prop; do not use an inline function.
tagName	Can be used to override the root HTML element rendered by the List component. The default value is "div", meaning that List renders an HTMLDivElement as its root. ⚠️ In most use cases the default ARIA roles are sufficient and this prop is not needed.

Grid

Renders data with many rows and columns.

ℹ️ Unlike List rows, Grid cell sizes must be known ahead of time. Either static sizes or something that can be derived (from the data in CellProps) without rendering.

Required props

Name	Description
cellComponent	React component responsible for rendering a cell. This component will receive columnIndex, rowIndex, and style props by default. Additionally it will receive prop values passed to cellProps. ℹ️ The prop types for this component are exported as CellComponentProps
cellProps	Additional props to be passed to the cell-rendering component. Grid will automatically re-render cells when values in this object change. ⚠️ This object must not contain ariaAttributes, columnIndex, rowIndex, or style props.
columnCount	Number of columns to be rendered in the grid.
columnWidth	Column width; the following formats are supported: number of pixels (number) percentage of the grid's current width (string) function that returns the column width (in pixels) given an index and cellProps ℹ️ Percentage widths can't be resolved during server rendering unless a defaultWidth (or a pixel width via the style prop) is specified.
rowCount	Number of rows to be rendered in the grid.
rowHeight	Row height; the following formats are supported: number of pixels (number) percentage of the grid's current height (string) function that returns the row height (in pixels) given an index and cellProps ℹ️ Percentage heights can't be resolved during server rendering unless a defaultHeight (or a pixel height via the style prop) is specified.

Optional props

Name	Description
className	CSS class name.
dir	Indicates the directionality of grid cells. ℹ️ The directionality of an ancestor element can't be detected during server rendering; specify this prop explicitly for server-rendered right-to-left grids. ℹ️ See HTML dir global attribute for more information.
style	Optional CSS properties. The grid of cells will fill the height and width defined by this style.
children	Additional content to be rendered within the grid (above cells). This property can be used to render things like overlays or tooltips.
columnKey	Grids use the column index as a key by default. This prop can be used along with the rowKey prop to provide a custom key value. ℹ️ Custom keys can ensure better UX for sortable or filterable grids, particularly if your cell components are stateful. Refer to the React documentation for more info. ⚠️ This prop cannot be auto-memoized because it is called during render. It is important to always useCallback for this prop; do not use an inline function.
defaultHeight	Default height of grid (in pixels) for initial render, before its actual height has been measured. ℹ️ Grids can't be measured during server rendering, so this value determines how many rows are server rendered. It's recommended to set this to the expected height of the grid (or to specify a pixel height via the style prop).
defaultScrollLeft	Initial horizontal scroll offset (in pixels) of the grid. This value is only applied once, when the grid first mounts with at least one column. ℹ️ Server-rendered HTML can't be pre-scrolled, so server rendering always starts at the first column; the default scroll offset is applied once the grid hydrates. ⚠️ If the grid can't be scrolled that far when the offset is applied (e.g. it is hidden with display: none, or uses percentage column widths before its width has been measured), the offset is clamped or ignored and not retried. Specify a defaultWidth (or a pixel width via the style prop) when using percentage column widths.
defaultScrollTop	Initial vertical scroll offset (in pixels) of the grid. This value is only applied once, when the grid first mounts with at least one row. ℹ️ Server-rendered HTML can't be pre-scrolled, so server rendering always starts at the first row; the default scroll offset is applied once the grid hydrates. ⚠️ If the grid can't be scrolled that far when the offset is applied (e.g. it is hidden with display: none, or uses percentage row heights before its height has been measured), the offset is clamped or ignored and not retried. Specify a defaultHeight (or a pixel height via the style prop) when using percentage row heights.
defaultWidth	Default width of grid (in pixels) for initial render, before its actual width has been measured. ℹ️ Grids can't be measured during server rendering, so this value determines how many columns are server rendered. It's recommended to set this to the expected width of the grid (or to specify a pixel width via the style prop).
gridRef	Imperative Grid API. ℹ️ The useGridRef and useGridCallbackRef hooks are exported for convenience in TypeScript projects.
onCellsRendered	Callback notified when the range of rendered cells changes.
onResize	Callback notified when the Grid's outermost HTMLElement resizes. This may be used to (re)scroll a cell into view.
overscanCount	How many additional rows/columns to render outside of the visible area. This can reduce visual flickering near the edges of a grid when scrolling.
rowKey	Grids use the row index as a key by default. This prop can be used along with the columnKey prop to provide a custom key value. ℹ️ Custom keys can ensure better UX for sortable or filterable grids, particularly if your cell components are stateful. Refer to the React documentation for more info. ⚠️ This prop cannot be auto-memoized because it is called during render. It is important to always useCallback for this prop; do not use an inline function.
tagName	Can be used to override the root HTML element rendered by the Grid component. The default value is "div", meaning that Grid renders an HTMLDivElement as its root. ⚠️ In most use cases the default ARIA roles are sufficient and this prop is not needed.