# ColumnGroup

> _Since v0.1.1_

Column group definition (computed at runtime) *

## Properties

| Property | Type | Description |
| -------- | ---- | ----------- |
| `id` | <code>string</code> | Unique group identifier |
| `label?` | <code>string</code> | Display label for the group header |
| `columns` | <code><a href="/grid/api/core/interfaces/columnconfig/">ColumnConfig</a>&lt;T&gt;[]</code> | Columns belonging to this group |
| `firstIndex` | <code>number</code> | Index of first column in this group |
| `renderer?` | <code>(params: <a href="/grid/plugins/grouping-columns/interfaces/groupheaderrenderparams/">GroupHeaderRenderParams</a>) =&gt; string &#124; void &#124; HTMLElement</code> | Per-group renderer. Resolved from the originating ColumnGroupDefinition.renderer when present. |