Compress images
under 50KB.
JPEG, PNG, WebP, and GIF — automatically optimized and scaled to stay under 50KB with maximum visual quality. 100% private, offline in your browser.
Drop your image here
JPEG · PNG · WebP · GIF · Max 50 MB
Quick Format
Conversion Settings
Why LessBytes is the Best Image Compressor
100% Offline & Private
Your files are processed entirely in your web browser. No uploads, no servers, absolute security for your images.
Bulk Compression
Process dozens of files at the same time. Customize individual image quality or apply bulk changes instantly.
Smart Resizing & Formats
Scale output dimensions, lock aspect ratios, and convert between JPEG, PNG, WebP, and GIF formats effortlessly.
Side-by-Side Comparison
Compare original and compressed versions side-by-side with our real-time interactive drag slider.
How to Compress Images Online for Free
Upload Your Images
Drag and drop your files or click Choose Files to select JPEG, PNG, WebP, or GIF files.
Optimize & Configure
Set global parameters or adjust individual cards to change quality, format, dimensions, or filters.
Compare & Verify
Drag the split-slider to check quality loss. Use our fullscreen view for fine details inspection.
Export & Download
Download individual optimized images directly, or compile them all in a single ZIP archive instantly.
Frequently Asked Questions
LessBytes runs 100% locally in your web browser. Unlike other tools that upload your private photos to external servers, LessBytes converts and compresses images entirely on your CPU/GPU, ensuring absolute data security while providing fast bulk adjustments and instant previews.
Yes, absolutely. Because the application utilizes HTML5 Canvas and browser JavaScript APIs locally, your images are never sent over the internet or saved to any cloud storage. You can even disconnect your internet and continue compressing images offline.
Yes. You can upload multiple images at the same time. You can choose to adjust settings globally for all images or open overrides for individual images. Finally, you can download all compressed files bundled in a single ZIP folder to avoid browser popup blocks.
We support JPEG, PNG, WebP, and GIF images for input and output. You can optimize, compress, and inter-convert between any of these formats (e.g., JPEG to WebP, WebP to PNG) inside the tool settings.
Setting your compression quality target between 80% and 90% is highly recommended. This reduces the file size of your images by up to 90% while keeping any loss in quality visually imperceptible to the human eye.