> For the complete documentation index, see [llms.txt](https://developers-apps-in-toss.toss.im/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-en/common/file-storage/file.md).

# Save file

### Saving files

**SDK function:** `saveBase64Data`

`saveBase64Data` This function saves Base64 data encoded as a string to the user's device with the specified file name and MIME type. It can save data in various formats such as images, text, and PDF.

**Signature**

```typescript
function saveBase64Data(params: SaveBase64DataParams): Promise<void>;
```

**Parameters**

* **params** · Required · `SaveBase64DataParams`

  An object containing the data to save and file information.

  * **params.data** · Required · `string`

    A Base64-encoded data string.
  * **params.fileName** · Required · `string`

    The name of the file to save. You should include the extension as well. For example, you can save it as 'example.png'.
  * **params.mimeType** · Required · `string`

    The MIME type of the file to save. For example, specifying 'image/png' means an image, and 'application/pdf' means a PDF file. For more details, see [MIME documentation](https://developer.mozilla.org/ko/docs/Web/HTTP/Guides/MIME_types).

**Example**

**Saving Base64 image data to the user's device**

{% tabs %}
{% tab title="js" %}

```js
import { saveBase64Data } from '@apps-in-toss/web-framework';

async function handleSaveBase64Data() {
  try {
    await saveBase64Data({
      data: 'iVBORw0KGgo...',
      fileName: 'some-photo.png',
      mimeType: 'image/png',
    });
    console.log('Data saved successfully');
  } catch (error) {
    console.error('Failed to save data:', error);
  }
}
```

{% endtab %}

{% tab title="React" %}

```tsx
import { saveBase64Data } from '@apps-in-toss/web-framework';
import { Button } from '@toss/tds-mobile';

function SaveButton() {
  const handleSave = async () => {
    try {
      await saveBase64Data({
        data: 'iVBORw0KGgo...',
        fileName: 'some-photo.png',
        mimeType: 'image/png',
      });
    } catch (error) {
      console.error('Failed to save data:', error);
    }
  };

  return <Button onClick={handleSave}>Save</Button>;
}
```

{% endtab %}

{% tab title="React Native" %}

```tsx
import { saveBase64Data } from '@apps-in-toss/framework';
import { Button } from '@toss/tds-react-native';

function SaveButton() {
  const handleSave = async () => {
    try {
      await saveBase64Data({
        data: 'iVBORw0KGgo...',
        fileName: 'some-photo.png',
        mimeType: 'image/png',
      });
    } catch (error) {
      console.error('Failed to save data:', error);
    }
  };

  return <Button onPress={handleSave}>Save</Button>;
}
```

{% endtab %}
{% endtabs %}


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