Image Compression Calculator
Optimize image file sizes
Original Image
Compression Settings
Size Comparison
Size Breakdown
Format Comparison
Format Comparison at Different Quality Levels
Estimated file sizes for a 1920×1080 image at different quality levels
| Quality | JPEG | WebP | AVIF | PNG | Best Format |
|---|
Format Characteristics
| Format | Compression | Transparency | Browser Support | Best For |
|---|---|---|---|---|
| JPEG | Lossy | No | Universal | Photos, complex images |
| WebP | Lossy/Lossless | Yes | Modern browsers | Web images, general use |
| AVIF | Lossy/Lossless | Yes | Limited (growing) | Best compression, future-proof |
| PNG | Lossless | Yes | Universal | Screenshots, graphics, logos |
Format Selection Tips
Photos
Use JPEG at 80-85% quality for best balance of size and quality
Web Images
Use WebP for modern browsers with JPEG fallback for compatibility
Best Quality
Use AVIF for best compression, but provide WebP/JPEG fallbacks
Graphics/Logos
Use PNG for sharp edges, text, and graphics with transparency
Understanding Image Compression
What is Image Compression?
Image compression reduces the file size of images by removing redundant data or using mathematical algorithms to represent the image more efficiently. There are two main types:
- Lossy Compression: Permanently removes some data to achieve smaller sizes. Quality degrades with higher compression (JPEG, WebP lossy, AVIF lossy)
- Lossless Compression: Reduces size without losing any data. Perfect quality preservation (PNG, WebP lossless, AVIF lossless)
Image Format Guide
Choosing the right format depends on your use case:
- JPEG: Best for photographs and complex images. Uses lossy compression. Does not support transparency
- WebP: Modern format by Google. 25-35% smaller than JPEG at same quality. Supports transparency and animation
- AVIF: Next-generation format. 50% smaller than JPEG. Excellent quality but limited browser support
- PNG: Lossless compression. Best for graphics, logos, screenshots. Supports transparency
- GIF: Limited to 256 colors. Supports animation. Being replaced by WebP/APNG
Compression Calculation
The basic formula for estimating compressed file size:
- Original Size = Width × Height × Bits per pixel / 8
- Compressed Size = Original Size × Compression Factor
- Compression Factor depends on format and quality (e.g., JPEG at 80% ≈ 0.1-0.2)
- Savings = Original Size - Compressed Size
Quality Settings
Recommended quality settings for different use cases:
- 90-95%: Maximum quality for print or professional work
- 80-85%: High quality for web use, good balance
- 70-75%: Medium quality, acceptable for most web images
- 50-65%: Low quality, use only for thumbnails or previews
Web Optimization Tips
- Resize first: Resize images to display size before compression
- Use modern formats: Serve WebP/AVIF with JPEG/PNG fallbacks
- Lazy loading: Load images only when they enter viewport
- CDN: Use CDN with automatic image optimization
- Responsive images: Use srcset for different screen sizes
- Cache properly: Set appropriate cache headers for images
Best Practices
Resize Before Compress
Always resize to display dimensions first. A 4K image displayed at 200px doesn't need 4K resolution
Use Multiple Formats
Serve AVIF → WebP → JPEG with HTML picture element for best compatibility
Monitor Performance
Use Lighthouse to check image optimization and page load performance
Progressive JPEG
Use progressive JPEG for better perceived loading on slow connections
Understanding Image Compression
Image compression is essential for web performance, reducing page load times and bandwidth usage. By choosing the right format and quality settings, you can dramatically reduce file sizes while maintaining acceptable visual quality.
Image Formats Comparison
Modern image formats offer different trade-offs:
- JPEG: Universal compatibility, good for photos, lossy compression
- WebP: 25-35% smaller than JPEG, supports transparency, modern browsers
- AVIF: 50% smaller than JPEG, best compression, growing support
- PNG: Lossless, perfect for graphics and text, larger file sizes
Quality Recommendations
Recommended quality settings for different use cases:
- 90-95%: Professional work, print quality
- 80-85%: Web images, good balance of quality and size
- 70-75%: Acceptable for most web use
- 50-65%: Thumbnails, previews only
Web Optimization Tips
Best practices for web image optimization:
- Resize first: Resize to display size before compression
- Use modern formats: Serve WebP/AVIF with fallbacks
- Lazy loading: Load images only when needed
- Responsive images: Use srcset for different screen sizes
- CDN: Use CDN with automatic optimization
Using This Calculator
Follow these steps:
- Step 1: Enter image dimensions (width × height)
- Step 2: Select original format (PNG, BMP, TIFF, or RAW)
- Step 3: Choose target format (JPEG, WebP, AVIF, or PNG)
- Step 4: Adjust quality level (10-100%)
- Step 5: Select resize factor if needed
- Step 6: View compressed size and savings
- Step 7: Check format comparison table
- Step 8: Read the guide for optimization tips
More Media & Design Tools
Explore more media and design calculators in our collection, including Video Bitrate Calculator and Color Code Converter!