> ## 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.

# Image Resizer

> Bulk resize images directly from File Explorer context menu

## Overview

Image Resizer is a Windows Shell Extension that enables quick batch resizing of images directly from File Explorer. Right-click on one or multiple images to resize them using predefined or custom dimensions without opening any image editing software.

<Tip>
  Image Resizer preserves EXIF metadata by default and can handle multiple image formats simultaneously.
</Tip>

## Activation

<Steps>
  <Step title="Enable Image Resizer">
    Open PowerToys Settings and enable **Image Resizer**
  </Step>

  <Step title="Select Images">
    In File Explorer, select one or more image files
  </Step>

  <Step title="Open Context Menu">
    Right-click on the selected images
  </Step>

  <Step title="Choose Resize Images">
    Click "Resize pictures" or "Resize images" option
  </Step>

  <Step title="Configure and Resize">
    Choose size preset or custom dimensions, then click Resize
  </Step>
</Steps>

## Key Features

### Batch Processing

<CardGroup cols={2}>
  <Card title="Multiple Files" icon="images">
    Resize hundreds of images at once

    Select all, right-click, resize
  </Card>

  <Card title="Mixed Formats" icon="file-image">
    Process different image formats together

    JPG, PNG, BMP, TIFF, GIF, TGA
  </Card>

  <Card title="Preserve Originals" icon="copy">
    Keep original files intact

    Creates new resized copies
  </Card>

  <Card title="Custom Output" icon="folder">
    Choose output location and naming

    Flexible file organization
  </Card>
</CardGroup>

### Size Presets

Built-in common image sizes:

<Tabs>
  <Tab title="Small">
    **Default: 854 × 480 pixels**

    * Social media thumbnails
    * Email attachments
    * Quick previews

    Customizable in settings
  </Tab>

  <Tab title="Medium">
    **Default: 1366 × 768 pixels**

    * Web images
    * Blog photos
    * Standard displays

    Good balance of quality and size
  </Tab>

  <Tab title="Large">
    **Default: 1920 × 1080 pixels**

    * HD displays
    * Presentations
    * Large web images

    Full HD resolution
  </Tab>

  <Tab title="Phone">
    **Default: 320 × 568 pixels**

    * Mobile wallpapers
    * App mockups
    * Phone-optimized images

    Portrait orientation
  </Tab>

  <Tab title="Custom">
    **User-defined dimensions**

    * Exact pixel dimensions
    * Percentage of original
    * Width or height only (maintain aspect)

    Maximum flexibility
  </Tab>
</Tabs>

### Resize Options

Multiple resizing modes:

```csharp theme={null}
// Resize modes available
public enum ResizeMode
{
    Fit,              // Fit within dimensions (default)
    Fill,             // Fill dimensions (may crop)
    Stretch,          // Stretch to exact dimensions
    ShrinkOnly,       // Only shrink, never enlarge
    Percentage        // Scale by percentage
}
```

<Tabs>
  <Tab title="Fit (Default)">
    Resize to fit within dimensions while maintaining aspect ratio:

    ```plaintext theme={null}
    Target: 1000×1000

    Input: 2000×1000   →  Output: 1000×500
    Input: 1000×2000   →  Output: 500×1000
    ```

    **Best for:** Preserving image proportions
  </Tab>

  <Tab title="Fill">
    Fill target dimensions, cropping if necessary:

    ```plaintext theme={null}
    Target: 1000×1000

    Input: 2000×1000   →  Output: 1000×1000 (cropped)
    Input: 1000×2000   →  Output: 1000×1000 (cropped)
    ```

    **Best for:** Fixed-size thumbnails
  </Tab>

  <Tab title="Stretch">
    Force exact dimensions:

    ```plaintext theme={null}
    Target: 1000×1000

    All inputs  →  Output: 1000×1000 (may distort)
    ```

    **Best for:** When exact size is required

    **Warning:** May distort images
  </Tab>

  <Tab title="Percentage">
    Scale by percentage:

    ```plaintext theme={null}
    Scale: 50%

    Input: 2000×1000   →  Output: 1000×500
    Input: 800×600     →  Output: 400×300
    ```

    **Best for:** Uniform scaling
  </Tab>
</Tabs>

### File Naming

Customizable output file names:

<ParamField path="naming_pattern" type="string" default="%1 (%2)">
  Output filename pattern

  **Tokens:**

  * `%1` - Original filename
  * `%2` - Size name (e.g., "Small", "Medium")
  * `%3` - Selected width
  * `%4` - Selected height
  * `%5` - Actual width
  * `%6` - Actual height
</ParamField>

**Examples:**

```plaintext theme={null}
Pattern: "%1 (%2)"
Input:   photo.jpg
Output:  photo (Medium).jpg

Pattern: "%1_%3x%4"
Input:   photo.jpg
Output:  photo_1920x1080.jpg

Pattern: "%1_resized"
Input:   photo.jpg  
Output:  photo_resized.jpg
```

### Format and Quality

<ParamField path="output_format" type="enum" default="Original">
  Output image format

  Options:

  * Original (maintain input format)
  * PNG
  * JPEG
  * BMP
  * TIFF
  * GIF
</ParamField>

<ParamField path="jpeg_quality" type="number" default="90">
  JPEG compression quality (1-100)

  Higher = better quality, larger file size
</ParamField>

<ParamField path="png_interlacing" type="boolean" default="false">
  Enable PNG interlacing for progressive loading
</ParamField>

<ParamField path="tiff_compression" type="enum" default="None">
  TIFF compression method

  Options: None, LZW, ZIP, CCITT
</ParamField>

### EXIF Data Preservation

```csharp theme={null}
// EXIF metadata handling
public class ImageResizerOptions
{
    public bool KeepExifData { get; set; } = true;
    
    // Preserved metadata:
    // - Camera make/model
    // - Date taken
    // - GPS coordinates
    // - Copyright information
    // - Image orientation
    // - Camera settings (ISO, aperture, etc.)
}
```

**Toggle in settings:** Option to remove EXIF data for privacy.

## Configuration

### Size Presets

Customize the built-in presets:

1. Open PowerToys Settings
2. Navigate to Image Resizer
3. Click "Edit" on any size preset
4. Modify dimensions and name
5. Add new custom sizes with "+"

**Example custom sizes:**

```plaintext theme={null}
Instagram Square:  1080 × 1080
Facebook Cover:    820 × 312
Twitter Header:    1500 × 500
YouTube Thumbnail: 1280 × 720
4K:                3840 × 2160
```

### Advanced Settings

<ParamField path="shrink_only" type="boolean" default="false">
  Only shrink images, never enlarge

  Prevents quality loss from upscaling
</ParamField>

<ParamField path="replace_original" type="boolean" default="false">
  Replace original files with resized versions

  **Warning:** Cannot be undone
</ParamField>

<ParamField path="ignore_orientation" type="boolean" default="false">
  Ignore EXIF orientation flag

  Use if images appear rotated
</ParamField>

<ParamField path="output_directory" type="string" default="Same as input">
  Where to save resized images

  Options:

  * Same folder as originals
  * Custom directory
  * Ask each time
</ParamField>

<ParamField path="encoder_parameters" type="advanced">
  Format-specific encoding options

  * JPEG: Quality, progressive
  * PNG: Compression level, interlacing
  * TIFF: Compression type
</ParamField>

## Use Cases

### Web Development

<AccordionGroup>
  <Accordion title="Optimize Website Images">
    Reduce image file sizes for faster loading:

    ```plaintext theme={null}
    1. Select all images for website
    2. Right-click → Resize images
    3. Choose "Medium" (1366×768)
    4. Set JPEG quality to 85%
    5. Resize → Upload optimized images
    ```

    **Result:** Faster page load times
  </Accordion>

  <Accordion title="Responsive Images">
    Create multiple sizes for responsive design:

    ```plaintext theme={null}
    # Create small, medium, large versions
    1. Resize to 640px width   (mobile)
    2. Resize to 1024px width  (tablet)
    3. Resize to 1920px width  (desktop)
    ```

    Use in HTML:

    ```html theme={null}
    <img
         src="image-1920.jpg" alt="...">
    ```
  </Accordion>
</AccordionGroup>

### Photography

<Steps>
  <Step title="Social Media Sharing">
    Resize photos for social platforms:

    **Instagram:**

    * Square: 1080×1080
    * Portrait: 1080×1350
    * Landscape: 1080×566

    **Facebook:**

    * Post: 1200×630
    * Cover: 820×312
  </Step>

  <Step title="Email Attachments">
    Reduce file size for email:

    1. Select photos
    2. Resize to "Small" or "Medium"
    3. JPEG quality 80-85%
    4. Attach resized versions (under 10MB total)
  </Step>

  <Step title="Print Preparation">
    Create print-ready sizes:

    * 4×6": 1800×1200 (300 DPI)
    * 5×7": 2100×1500 (300 DPI)
    * 8×10": 3000×2400 (300 DPI)
  </Step>
</Steps>

### E-commerce

<CardGroup cols={2}>
  <Card title="Product Images">
    Standardize product photo dimensions

    Consistent sizing across catalog
  </Card>

  <Card title="Thumbnails">
    Create grid thumbnails

    Square format for category pages
  </Card>

  <Card title="Zoom Images">
    Multiple resolution versions

    Small preview + large zoom view
  </Card>

  <Card title="Mobile Optimization">
    Mobile-friendly image sizes

    Reduce bandwidth usage
  </Card>
</CardGroup>

### Content Creation

<Tabs>
  <Tab title="Blog Images">
    Prepare blog post images:

    ```plaintext theme={null}
    Featured image: 1200×630 (2:1 ratio)
    Inline images:  800×600 or 800×450
    Thumbnails:     400×300
    ```
  </Tab>

  <Tab title="Presentations">
    Resize images for PowerPoint/Keynote:

    ```plaintext theme={null}
    Full slide:  1920×1080 (16:9)
    Half slide:  960×1080
    Quarter:     960×540
    ```
  </Tab>

  <Tab title="Video Thumbnails">
    YouTube/Vimeo thumbnails:

    ```plaintext theme={null}
    YouTube:  1280×720 (16:9)
    Vimeo:    1280×720
    ```
  </Tab>
</Tabs>

## Technical Details

### Architecture

```mermaid theme={null}
graph TD
    A[File Explorer] --> B[Context Menu]
    B --> C[Image Resizer UI]
    C --> D[Resize Engine]
    D --> E[Image Decoder]
    E --> F[WIC - Windows Imaging Component]
    D --> G[Resize Algorithm]
    G --> H[Image Encoder]
    H --> F
    F --> I[Output Files]
```

### Windows Imaging Component

Image Resizer uses Windows Imaging Component (WIC):

```cpp theme={null}
// WIC-based image processing
IWICImagingFactory* factory;
IWICBitmapDecoder* decoder;
IWICBitmapFrameDecode* frame;
IWICBitmapScaler* scaler;
IWICBitmapEncoder* encoder;

// High-quality resizing
scaler->Initialize(
    frame,
    newWidth,
    newHeight,
    WICBitmapInterpolationModeFant  // High-quality Fant algorithm
);
```

**Benefits:**

* Native Windows support
* Hardware acceleration
* High-quality algorithms
* Codec extensibility

### Supported Formats

| Format   | Read | Write | Notes                        |
| -------- | ---- | ----- | ---------------------------- |
| **JPEG** | ✓    | ✓     | Adjustable quality           |
| **PNG**  | ✓    | ✓     | Lossless, alpha support      |
| **BMP**  | ✓    | ✓     | Large file sizes             |
| **TIFF** | ✓    | ✓     | Multiple compression options |
| **GIF**  | ✓    | ✓     | Animation preserved          |
| **TGA**  | ✓    | ✓     | Truevision Targa             |
| **WDP**  | ✓    | ✓     | Windows Media Photo          |
| **HEIC** | ✓    | ✗     | Read-only (requires codec)   |

### Resize Quality

Interpolation algorithms:

```cpp theme={null}
enum WICBitmapInterpolationMode
{
    WICBitmapInterpolationModeNearestNeighbor,  // Fastest, lowest quality
    WICBitmapInterpolationModeLinear,           // Fast, good for thumbnails
    WICBitmapInterpolationModeCubic,            // Good quality/speed balance
    WICBitmapInterpolationModeFant              // Highest quality (default)
};
```

**Image Resizer uses Fant algorithm** for best quality.

### Project Structure

```plaintext theme={null}
src/modules/imageresizer/
├─ ImageResizerCLI/           # Command-line interface
├─ ImageResizerContextMenu/  # Shell extension (C++)
├─ ImageResizerLib/          # Core resize logic
└─ ui/                       # Resize dialog UI (C#)
```

**Source:** `src/modules/imageresizer/README.md`

## Keyboard Shortcuts

### In Resize Dialog

| Shortcut | Action                       |
| -------- | ---------------------------- |
| `Enter`  | Resize with current settings |
| `Esc`    | Cancel and close dialog      |
| `Tab`    | Navigate between options     |
| `Alt+S`  | Toggle size dropdown         |
| `Alt+R`  | Resize button                |

## Troubleshooting

<AccordionGroup>
  <Accordion title="Context menu option not appearing">
    **Check:**

    * Image Resizer enabled in PowerToys Settings
    * Selected files are image formats
    * On Windows 11, check "Show more options"

    **Fix:**

    1. Restart File Explorer
    2. Disable and re-enable Image Resizer
    3. Restart PowerToys
    4. Check shell extension registration
  </Accordion>

  <Accordion title="Resize fails or produces errors">
    **Possible causes:**

    * Insufficient disk space
    * Output directory not writable
    * Image file corrupted
    * Filename too long

    **Solutions:**

    1. Check available disk space
    2. Verify output directory permissions
    3. Try resizing one image to identify problem file
    4. Use shorter filename pattern
  </Accordion>

  <Accordion title="Output images poor quality">
    **Improve quality:**

    1. Increase JPEG quality setting (90-95)
    2. Use PNG for lossless quality
    3. Don't enlarge small images
    4. Enable "Shrink only" to prevent upscaling
    5. Use appropriate resize mode (Fit, not Stretch)

    **Note:** Upscaling always reduces quality
  </Accordion>

  <Accordion title="EXIF data lost after resize">
    **Preserve metadata:**

    1. Open Image Resizer settings
    2. Enable "Keep EXIF data"
    3. Resize images again

    **Note:** Some formats don't support EXIF (BMP, GIF)

    **Alternative:** Use EXIF tools to copy metadata
  </Accordion>

  <Accordion title="Very slow for many images">
    **Performance tips:**

    * Process in smaller batches (50-100 images)
    * Close other applications
    * Use SSD instead of HDD
    * Disable antivirus temporarily
    * Reduce output quality slightly

    **Note:** Processing hundreds of large RAW files takes time
  </Accordion>
</AccordionGroup>

## Best Practices

<Tip>
  **Quality vs File Size:**

  * **Web images**: JPEG 80-85 quality, 1920px max width
  * **Thumbnails**: JPEG 75 quality, 400px max
  * **Archival**: PNG lossless or JPEG 95 quality
  * **Screenshots**: PNG lossless
  * **Photos with text**: PNG or high JPEG quality
</Tip>

### Batch Processing Tips

1. **Test First**: Resize one image to verify settings
2. **Backup Originals**: Keep original files safe
3. **Consistent Naming**: Use clear filename patterns
4. **Organize Output**: Use subfolders for different sizes
5. **Document Settings**: Note what presets/settings you used

### Format Selection

```plaintext theme={null}
Choose format based on content:

✓ JPEG:  Photos, complex images, gradients
✓ PNG:   Screenshots, logos, transparency, text
✗ BMP:   Avoid (large files, no benefits)
✓ TIFF:  Professional/archival (with LZW compression)
✗ GIF:   Avoid for photos (256 colors max)
```

## See Also

* [File Explorer Add-ons](/utilities/file-explorer-addons) - Preview images
* [PowerToys Run](/utilities/powertoys-run) - Quick file operations
* [Color Picker](/utilities/color-picker) - Sample image colors