Image Resizer

Key Features:

• Professional-Grade Algorithms: Uses Lanczos3 filter with unsharp masking for the highest quality results
• Drag & Drop Support: Simply drag images onto the page or click to upload
• Precise Control: Set exact width and height in pixels
• Aspect Ratio Lock: Maintain proportions automatically when resizing
• Quick Presets: Instantly resize to 50%, 75%, 150%, or 200% of original size
• Multiple Formats: Output as JPEG, PNG, or WebP
• Algorithm Selection: Choose between Lanczos3, Lanczos2, or Box filtering
• Quality Control: Adjust compression quality for JPEG and WebP
• Real-time Preview: See the resized image before downloading
• File Size Comparison: View before and after file sizes with percentage change
• Complete Privacy: All processing happens in your browser - no uploads

Resize Algorithms:

• Lanczos3 (Recommended): The highest quality algorithm using a 3-lobed Lanczos filter. Best for downscaling, produces sharp and crisp results with minimal artifacts. Includes unsharp masking for enhanced detail.
• Lanczos2: Faster than Lanczos3 with still excellent quality. Good balance between speed and quality for most use cases.
• Box: Fastest algorithm but lower quality. Suitable for quick previews or when speed is more important than quality.

All algorithms preserve alpha channel transparency and use unsharp masking to enhance edge definition.

Supported Formats:

• Input: JPEG, PNG, WebP, GIF, and most common image formats
• Output: JPEG (lossy, smaller files), PNG (lossless, transparency), WebP (modern, efficient)

Common Use Cases:

• Web Optimization: Resize images for faster website loading
• Social Media: Prepare images for Instagram, Facebook, Twitter profiles and posts
• Email: Reduce image size for email attachments
• Thumbnails: Create smaller preview versions of images
• Blog Posts: Optimize images for content management systems
• Product Photos: Standardize product image dimensions for e-commerce
• Profile Pictures: Resize images for avatars and profile photos

How to Use:

1. Upload: Drag and drop an image or click to select from your device
2. Set Dimensions: Enter desired width and height, or use quick resize presets
3. Adjust Settings: Choose output format and quality (for JPEG/WebP)
4. Resize: Click "Resize Image" to process
5. Preview: Review the resized image and file size
6. Download: Click "Download" to save the resized image

Tips for Best Results:

• Aspect Ratio: Keep "Maintain aspect ratio" checked to avoid distortion
• Algorithm Choice: Use Lanczos3 for maximum quality when downscaling photos. Use Box for quick previews.
• Upscaling: Enlarging images beyond original size may reduce quality. Lanczos filters help minimize blur when upscaling.
• Format Selection: Use JPEG for photos, PNG for graphics with transparency, WebP for best compression
• Quality Setting: 80-90% quality offers good balance between size and quality
• Web Images: 1920px width is typically sufficient for full-width web images
• Processing Time: Lanczos3 is slower but worth the wait for best quality. The difference is most noticeable with large images.

Privacy & Security:

Your privacy is our priority. All image processing happens entirely in your browser using the HTML5 Canvas API. Images are never uploaded to any server, and no data leaves your device. You can even use this tool offline once the page is loaded.