> ## Documentation Index
> Fetch the complete documentation index at: https://dripart-docs-custom-nodes-sdk-v2-frontend.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# MaskPreview - ComfyUI Built-in Node Documentation

> The MaskPreview node displays a visual preview of the mask data directly in the ComfyUI interface, without saving it to the output directory.

The MaskPreview node displays a visual preview of the mask data directly in the ComfyUI interface, without saving it to the output directory. This lets you inspect the exact mask values at any point in your workflow.

## Inputs

| Parameter         | Description                                                      | Data Type      | Required | Range |
| ----------------- | ---------------------------------------------------------------- | -------------- | -------- | ----- |
| `mask`            | The mask data to preview                                         | MASK           | Yes      | -     |
| `filename_prefix` | Prefix for the preview filename (default: "ComfyUI")             | STRING         | No       | -     |
| `prompt`          | Prompt information for metadata (automatically provided)         | PROMPT         | No       | -     |
| `extra_pnginfo`   | Additional PNG information for metadata (automatically provided) | EXTRA\_PNGINFO | No       | -     |

The `prompt` and `extra_pnginfo` inputs are hidden and are supplied automatically by the ComfyUI system; you do not need to connect them manually.

## Outputs

| Output Name | Description                                                                          | Data Type |
| ----------- | ------------------------------------------------------------------------------------ | --------- |
| `mask`      | The mask data that was previewed, returned unchanged for further use in the workflow | MASK      |

> This documentation was AI-generated. If you find any errors or have suggestions for improvement, please feel free to contribute! [Edit on GitHub](https://github.com/Comfy-Org/embedded-docs/blob/main/comfyui_embedded_docs/docs/MaskPreview/en.md)

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