Image Resizer
Resize and scale images online for free. Adjust dimensions, maintain aspect ratios, crop photos, and batch process multiple images. Supports JPG, PNG, WebP, GIF. 100% browser-based - your images never leave your device.
Click or drag images to resize
Supports JPG, PNG, WebP, GIF, BMP. Up to 50MB each.
Resize Settings
Professional Image Resizing Made Simple
Whether you're preparing images for social media, optimizing photos for web use, creating thumbnails, or adjusting dimensions for print, our Image Resizer provides the perfect solution. Built with modern HTML5 Canvas technology, this tool processes your images entirely in your browser - no uploads, no servers, complete privacy.
Image resizing is one of the most common image manipulation tasks. Different platforms require different dimensions: Instagram prefers 1080x1080 for square posts, Twitter recommends 1600x900 for shared images, YouTube thumbnails should be 1280x720, and email newsletters work best with images under 600px wide. Rather than juggling multiple tools or complex software, our resizer handles all scenarios with ease.
The tool supports multiple resize modes to fit your specific needs: Fit mode ensures images stay within maximum dimensions while maintaining proportions, Fill mode creates exact dimensions by intelligently cropping, Cover mode fills the area while preserving aspect ratio, Scale mode adjusts by percentage, and Exact mode provides precise control when distortion is acceptable.
How to Resize Images: Step-by-Step Guide
Upload Your Images
Click the upload area or drag and drop your images. We support JPG, PNG, WebP, GIF, and BMP formats up to 50MB each. Select multiple files to batch resize with identical settings.
Set Target Dimensions
Enter your desired width and/or height in pixels. Leave one dimension empty to calculate it automatically based on aspect ratio. The lock icon toggles linked proportions.
Choose Resize Mode
Select how you want the image resized: Fit (contains within bounds), Fill (covers exact dimensions), Cover (fills maintaining ratio), Scale (percentage-based), or Exact (precise dimensions).
Download Resized Images
Preview the results in the queue. Download individual images or use "Download All" to get a ZIP archive of all resized images. Original filenames are preserved with "_resized" added.
Powerful Features for Every Use Case
100% Private & Secure
All image processing happens in your browser. Nothing is uploaded to our servers. Perfect for confidential photos, client work, or sensitive documents.
Instant Processing
Browser-based resizing means no upload or download delays. Resize images in seconds. Process dozens of images simultaneously with batch mode.
Smart Aspect Ratio
Automatically maintain proportions to prevent distortion. Lock dimensions together or adjust independently for complete control over image dimensions.
Multiple Resize Modes
Five resize modes for different scenarios: Fit for thumbnails, Fill for profile pictures, Cover for backgrounds, Scale for proportional adjustments, Exact for precise control.
Batch Processing
Resize unlimited images at once with the same settings. Our queue system tracks progress for each image. Download all as one convenient ZIP file.
Format Conversion
Convert between JPEG, PNG, and WebP while resizing. Optimize file format alongside dimensions for maximum efficiency and compatibility.
Understanding Resize Modes
Choosing the right resize mode is crucial for achieving the desired result. Each mode handles aspect ratios and dimensions differently to suit specific use cases.
| Mode | Behavior | Aspect Ratio | Best For |
|---|---|---|---|
| Fit | Image fits within bounds | Maintained | Thumbnails, galleries |
| Fill | Covers exact dimensions | Maintained (crops) | Profile pictures, cards |
| Cover | Fills area maintaining ratio | Maintained | Hero images, banners |
| Scale | Percentage-based scaling | Maintained | Proportional adjustments |
| Exact | Precise dimensions | Can be changed | Specific requirements |
Common Use Cases
Social Media
- Resize for Instagram posts (1080x1080)
- Optimize for Facebook covers (820x312)
- Create Twitter headers (1500x500)
- Prepare LinkedIn banners (1584x396)
- Format YouTube thumbnails (1280x720)
Web Development
- Create responsive image variants
- Generate thumbnail versions
- Optimize hero images for performance
- Prepare retina display assets
- Batch resize product images
Email & Marketing
- Size images for email newsletters (600px)
- Create email signature graphics
- Prepare banner ads (various sizes)
- Optimize for email attachments
- Format promotional graphics
Print & Documents
- Prepare images for print (300 DPI)
- Resize for document layouts
- Create standard photo sizes (4x6, 5x7)
- Format for presentations
- Adjust passport photo dimensions
Always Start with High Quality
Begin with the highest resolution source image. Downsizing preserves quality, but upsizing can't add detail that wasn't there originally.
Use Fit Mode for Consistency
When batch resizing images of different aspect ratios, Fit mode ensures all images stay within your maximum dimensions without cropping.
Consider Your Platform
Different platforms have optimal dimensions. Instagram prefers 1:1 square, while Twitter works best with 16:9 landscape orientation.
Maintain Aspect Ratio
Unless you need exact dimensions, always maintain aspect ratio to prevent distortion. People and faces are especially sensitive to stretching.
Mind the File Size
Smaller dimensions mean smaller file sizes. If your goal is optimization, combine resizing with our Image Compressor for maximum reduction.
Test at Display Size
Always preview resized images at their intended display size. What looks good at 100% zoom may have different perception at actual usage.
How Our Resizer Works
Our image resizer uses the HTML5 Canvas API with advanced interpolation algorithms. When you upload an image, it's loaded into a canvas element where we can manipulate every pixel. For downsizing, we use bilinear interpolation for smooth results. For upsizing, bicubic interpolation provides better quality by considering more surrounding pixels.
The "High Quality" option enables additional antialiasing and smoothing for professional results, though it takes slightly longer to process. This is especially important when creating thumbnails or significantly downsizing images, as it prevents jagged edges and maintains detail.
For batch processing, images are resized sequentially with progress tracking. The same settings apply to all images, making it easy to maintain consistency across large collections. JSZip packages multiple images for convenient download.
Image Dimensions and Web Performance
Properly sized images are critical for website performance. An image with 4000x3000 pixel dimensions displayed at 400x300 pixels wastes 90% of the bandwidth. Users download all those extra pixels even though they're never displayed.
- Page Load Speed: Smaller images load faster, improving user experience and reducing bounce rates. Google considers page speed a ranking factor.
- Bandwidth Savings: Properly sized images can reduce bandwidth by 60-80%. This matters for mobile users on limited data plans and reduces hosting costs.
- Core Web Vitals: LCP (Largest Contentful Paint) measures how quickly the main content loads. Oversized images directly hurt this metric.
- Mobile Experience: Mobile devices have smaller screens but often receive the same large images as desktops. Responsive images sized for device save bandwidth.
- SEO Benefits: Fast-loading pages rank higher in search results. Google's mobile-first indexing prioritizes sites optimized for mobile performance.
- User Retention: 53% of mobile users abandon sites that take over 3 seconds to load. Image optimization is often the quickest win for performance.
Frequently Asked Questions
How do I resize an image?
Are my images uploaded to your server?
What image formats are supported?
What is the difference between resize modes?
Fill: Image fills exact dimensions, cropping if needed.
Cover: Image covers area maintaining ratio.
Scale: Image scales proportionally by percentage.
Exact: Image resized to exact dimensions without maintaining ratio.