Compress JPEG Online
Reduce JPEG file size using MozJPEG — the best JPEG encoder. 100% private, no upload.
Your files never leave your device
How JPEG Compression Works
img.awajis uses MozJPEG, Mozilla's optimized JPEG encoder compiled to WebAssembly. MozJPEG produces files 5-10% smaller than standard JPEG encoders at the same visual quality. All processing runs directly in your browser — your images are never uploaded to any server.
When to Use JPEG
JPEG is ideal for photographs and images with smooth color gradients. It uses lossy compression, meaning some data is discarded to achieve smaller sizes. At quality 80, most images look indistinguishable from the original while being 60-80% smaller.
Quality Settings Guide
- 95: Near-lossless. Minimal size reduction but preserves fine details.
- 80: Recommended. Excellent quality with significant size savings.
- 60: Good for web thumbnails. Visible artifacts on close inspection.
Want even smaller files? Try converting to WebP for 25-35% more savings, or batch compress multiple images at once.