---
url: /process-functions/workbook-converttobase64.md
description: Encodes an Apache POI workbook as base64.
---

# workbook.convertToBase64 

::: warning Deprecated
Use [`ExcelWorkbook.toBase64()`](/process-functions/excel-workbook#tobase64) instead.
:::

Encodes an Apache POI workbook, from [workbook.create](/process-functions/workbook-create) or [workbook.open](/process-functions/workbook-open), as base64.

```js
workbook.convertToBase64(workbookObj)
```

## Parameters

| Parameter | Type | Description |
|---|---|---|
| `workbookObj` | `object` | The workbook to encode. |

## Returns

The workbook, base64-encoded.

## Examples

```js
const base64 = workbook.convertToBase64(wb);
```