Compress JPEG Images Online — Free & Private

Shrink JPEG file sizes using the mozjpeg encoder directly in your browser. No uploads, no server processing — your images stay on your device. Batch compress multiple files, fine-tune quality, and optionally convert to WebP for even smaller files.

Drag & drop JPEG files here or

Supports .jpg and .jpeg files

80%
Convert to WebP

Compressing...

Compressed Images

Compress JPEG Images Without Losing Quality

This free JPEG compressor uses mozjpeg, the same advanced encoder trusted by tech companies worldwide. Unlike basic compressors, mozjpeg uses trellis quantization and optimized Huffman coding to produce files 25–35% smaller than standard JPEG compression at the same visual quality.

How to Compress JPEG Files

  1. Drag and drop your JPEG files onto the upload area, or click to browse.
  2. Adjust the quality slider — 80 is ideal for most use cases.
  3. Click Compress JPEG and wait for processing to finish.
  4. Download files individually or all at once as a ZIP.

100% Private — Your Images Never Leave Your Device

Everything runs directly in your browser using WebAssembly. No files are uploaded to any server, ever. This means your photos stay completely private, and the tool works even after you go offline.

When to Use JPEG Compression

JPEG is the best format for photographs, product images, and any image with smooth gradients. Use this tool before uploading images to your website, email, or social media to reduce load times and save bandwidth. For graphics with transparency, use our PNG compressor instead.

FAQ

Frequently Asked Questions

This tool uses the mozjpeg encoder compiled to WebAssembly, running entirely in your browser. Mozjpeg is the same open-source library used by major CDNs and image optimization services. It applies advanced JPEG compression techniques — optimized Huffman coding, trellis quantization, and progressive encoding — to reduce file size significantly while preserving visual quality.

No. All compression happens locally on your device using WebAssembly technology. Your JPEG files are never transmitted, uploaded, stored, or accessed by any server. This means your photos stay completely private, the tool works offline after the initial page load, and there are no file size restrictions from server limits.

There is no enforced file size limit since all processing happens in your browser. However, very large files (20MB+ per image or high-resolution camera RAW exports saved as JPEG) require more memory and processing time. Most photos compress quickly. If you experience slowdowns with very large files, close other browser tabs to free up memory or compress in smaller batches.

Typical JPEG files can be reduced by 40-70% at the default quality setting of 80%. Photos taken with smartphones often see the largest reductions because camera apps prioritize speed over compression efficiency. Mozjpeg recompresses the image data far more efficiently. The exact savings depend on the original image content and how it was initially compressed.

The default 80% quality is ideal for most uses — web publishing, email attachments, social media. For professional photography or print-quality images, use 85-95%. For maximum file size reduction where some quality loss is acceptable (thumbnails, previews), try 60-75%. Below 50%, visible compression artifacts typically appear in smooth gradients and sharp edges.