> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/microsoft/powertoys/llms.txt
> Use this file to discover all available pages before exploring further.

# Peek

> A file previewer utility that lets you preview files instantly with a single keystroke without opening them in full applications.

Peek is a quick file previewer that lets you view file contents instantly without launching full applications. Press the activation shortcut while selecting files in File Explorer to get an immediate preview.

## Activation

<Steps>
  <Step title="Select Files">
    In File Explorer, select one or more files you want to preview.
  </Step>

  <Step title="Activate Peek">
    Press `Ctrl + Space` to open the Peek preview window.
  </Step>

  <Step title="Close Preview">
    Press `Esc` or `Ctrl + Space` again to close.
  </Step>
</Steps>

<Note>
  Peek works exclusively within File Explorer. The activation shortcut has no effect in other applications.
</Note>

## Supported File Types

Peek uses a previewer architecture to support different file formats. Each previewer implements the `IPreviewer` interface from `/src/modules/peek/Peek.FilePreviewer/Previewers/Interfaces/IPreviewer.cs`.

### Image Files

Preview images with support for:

* Common formats: PNG, JPG, GIF, BMP, TIFF, ICO
* Advanced formats: WebP, SVG
* RAW camera formats (through Windows codecs)
* Animated GIFs

**Features:**

* Zoom and pan support
* Display image dimensions and file size
* EXIF metadata display (for supported formats)

### Video Files

Preview video files using Windows Media Foundation:

* MP4, AVI, MKV, MOV, WMV
* MPEG, FLV, WebM
* Display duration, resolution, codec information
* Basic playback controls

### Audio Files

Preview audio files with:

* MP3, WAV, FLAC, AAC, OGG, WMA
* Display duration, bitrate, sample rate
* Waveform visualization
* Playback controls

Implementation: `/src/modules/peek/Peek.FilePreviewer/Controls/AudioControl.xaml.cs`

### Archive Files

Browse archive contents without extraction:

* ZIP, RAR, 7Z, TAR, GZ
* Display folder structure
* Show file count and sizes
* Preview individual files within archives

Implementation: `/src/modules/peek/Peek.FilePreviewer/Controls/ArchiveControl.xaml.cs`

### Code & Text Files

Syntax-highlighted preview for:

* Programming languages: C#, C++, JavaScript, Python, Java, Go, Rust, etc.
* Markup: HTML, XML, JSON, YAML, TOML
* Scripts: PowerShell, Bash, Batch
* Configuration files
* Plain text

### PDF Files

Preview PDF documents with:

* Page navigation
* Zoom controls
* Multi-page support
* Text selection

### Office Documents

Preview Microsoft Office files:

* Word (.docx, .doc)
* Excel (.xlsx, .xls)
* PowerPoint (.pptx, .ppt)

Uses Windows Shell preview handlers.

### Web Files

Preview web content:

* HTML files with rendering
* CSS files with syntax highlighting
* JavaScript files

Implementation: `/src/modules/peek/Peek.FilePreviewer/Controls/BrowserControl.xaml.cs`

### Special Folders & Drives

Preview drives and special folders with:

* Disk space information
* Drive type and file system
* Folder metadata

Implementation: `/src/modules/peek/Peek.FilePreviewer/Controls/DriveControl.xaml.cs`

## Features

### Multi-File Preview

<Tabs>
  <Tab title="Single File">
    Select one file and press `Ctrl + Space` to preview it in a centered window.
  </Tab>

  <Tab title="Multiple Files">
    Select multiple files in File Explorer:

    * Use arrow keys to navigate between selected files
    * File counter shows current position (e.g., "1 of 5")
    * Preview updates instantly when switching files
  </Tab>
</Tabs>

### Preview States

Peek implements state management through the `PreviewState` enum:

<CodeGroup>
  ```csharp States theme={null}
  public enum PreviewState
  {
      Uninitialized,  // Preview not yet started
      Loading,        // Loading file content
      Loaded,         // Successfully loaded
      Error,          // Failed to preview
  }
  ```
</CodeGroup>

From `/src/modules/peek/Peek.FilePreviewer/Previewers/Interfaces/IPreviewer.cs:24-30`

### Window Features

<Accordion title="Title Bar">
  Custom title bar with:

  * File name display
  * File path
  * Close button
  * Drag to move window

  Implementation: `/src/modules/peek/Peek.UI/Views/TitleBar.xaml`
</Accordion>

<Accordion title="Unsupported Files">
  When a file type isn't supported, Peek displays:

  * File icon
  * File name and path
  * File size
  * Modification date
  * Option to open in default application

  Implementation: `/src/modules/peek/Peek.UI/Views/UnsupportedFile.xaml`
</Accordion>

### File Actions

<Steps>
  <Step title="Copy File Path">
    Right-click or use context menu to copy the file path to clipboard.
  </Step>

  <Step title="Open in Default App">
    Click "Open" button to launch the file in its default application.
  </Step>

  <Step title="Open File Location">
    Quickly navigate to the file's containing folder.
  </Step>
</Steps>

## Configuration

### Activation Shortcut

Customize the activation shortcut in PowerToys Settings:

1. Open PowerToys Settings
2. Navigate to Peek
3. Change "Activation shortcut" (default: `Ctrl + Space`)

<Warning>
  Avoid conflicts with other applications. Common alternatives: `Ctrl + Shift + Space`, `Alt + P`
</Warning>

### Preview Settings

<AccordionGroup>
  <Accordion title="Window Size">
    Configure default preview window dimensions and position.
  </Accordion>

  <Accordion title="Previewer Options">
    Enable or disable specific previewers:

    * Disable resource-intensive previewers (video, large images)
    * Control which file types trigger preview
  </Accordion>

  <Accordion title="Performance">
    * Max file size for preview
    * Loading timeout
    * Memory limits for large files
  </Accordion>
</AccordionGroup>

## Use Cases

<CardGroup cols={2}>
  <Card title="Quick Inspection" icon="magnifying-glass">
    Verify file contents without opening apps - perfect for checking downloads, screenshots, or documents.
  </Card>

  <Card title="Archive Browsing" icon="file-zipper">
    Browse ZIP/archive contents without extraction. Navigate folder structures and preview files inside.
  </Card>

  <Card title="Code Review" icon="code">
    Quickly scan source code files with syntax highlighting. Review changes across multiple files.
  </Card>

  <Card title="Media Management" icon="photo-film">
    Preview images, videos, and audio files instantly while organizing media libraries.
  </Card>
</CardGroup>

## Keyboard Shortcuts

| Shortcut       | Action                                   |
| -------------- | ---------------------------------------- |
| `Ctrl + Space` | Open/Close Peek (default)                |
| `Esc`          | Close preview window                     |
| `←` `→`        | Navigate between multiple selected files |
| `Ctrl + C`     | Copy file path                           |
| `Ctrl + O`     | Open in default application              |
| `Ctrl + W`     | Close window                             |

## Advanced Features

### Shell Preview Handler Integration

Peek integrates with Windows Shell Preview Handlers for file types without native previewers:

```
Implementation: /src/modules/peek/Peek.FilePreviewer/Controls/ShellPreviewHandlerControl.xaml.cs
```

This enables preview support for:

* Third-party file formats with installed preview handlers
* Custom file types
* Fallback for unsupported formats

### WinUI 3 Architecture

Peek is built on WinUI 3 (Windows App SDK) for modern UI:

<CodeGroup>
  ```xml Project Configuration theme={null}
  <PropertyGroup>
    <UseWinUI>true</UseWinUI>
    <WindowsAppSDKSelfContained>true</WindowsAppSDKSelfContained>
    <OutputType>WinExe</OutputType>
  </PropertyGroup>
  ```
</CodeGroup>

From `/src/modules/peek/Peek.UI/Peek.UI.csproj:15, 22`

### Preview Size Calculation

Each previewer implements `GetPreviewSizeAsync()` to calculate optimal window dimensions:

```csharp theme={null}
Task<PreviewSize> GetPreviewSizeAsync(CancellationToken cancellationToken);
```

This ensures previews are sized appropriately for content type and screen resolution.

## Performance Considerations

<Tip>
  For optimal performance with large files:

  1. Set maximum file size limits in settings
  2. Disable video preview for very large video files
  3. Use timeout settings to prevent hanging on slow drives
  4. Peek processes previews asynchronously to avoid blocking File Explorer
</Tip>

## Troubleshooting

<AccordionGroup>
  <Accordion title="Preview Not Showing">
    * Ensure Peek is enabled in PowerToys Settings
    * Verify file type is supported
    * Check activation shortcut isn't conflicting with other apps
    * Restart File Explorer if Peek stops responding
  </Accordion>

  <Accordion title="Slow Preview Loading">
    * Large files may take time to load
    * Check if file is on network drive or slow storage
    * Reduce maximum file size in settings
  </Accordion>

  <Accordion title="Some Files Show 'Unsupported'">
    * File type may not have a built-in previewer
    * Install Windows codec packs for additional format support
    * Some proprietary formats require native applications
  </Accordion>
</AccordionGroup>

## Source Code

Location: `/src/modules/peek/`

* Main UI: `Peek.UI/`
* File previewers: `Peek.FilePreviewer/`
* Common utilities: `Peek.Common/`
* Project file: `Peek.UI/Peek.UI.csproj`