Offline Image Compressor & Resizer
Compress and resize JPG, PNG, and WebP images client-side in your browser using HTML5 Canvas.
Drag & Drop Image Here
JPG, PNG, WebP, or GIF (Up to 30MB) • Processed 100% in your browser
Visual Output Preview
🔒 100% In-Browser Canvas Re-encoding
Unlike commercial image compression services that transmit your personal photographs and proprietary assets across cloud networks, this tool processes images entirely using your browser's native HTML5 Canvas engine. Your images never leave your computer or phone.
About this tool
How to use it
- Drop an image into the upload dropzone or click 'Choose Image File' (or test immediately with the preloaded sample).
- Choose your target format: WebP (recommended for web performance), JPEG, or PNG.
- Adjust the quality slider (70-80% provides massive file savings with virtually zero visible degradation).
- Set max width and height dimensions with proportional aspect ratio lock enabled.
- Inspect the file size savings percentage and click 'Compress & Download Image'.
Why it matters
Uncompressed camera photos and high-resolution screenshots often weigh 5MB to 15MB, slowing down websites, consuming mobile cellular data, and exceeding email attachment limits. In-browser canvas re-encoding reduces file sizes by up to 90% in milliseconds.
When to use it
Use this tool to optimize photos before uploading to WordPress/Shopify, resize profile avatars, prepare images for email attachments, or convert heavy PNGs to lightweight WebPs.
Good to know
Powered by HTML5 Canvas API and client-side toBlob() encoding with high-bicubic smoothing algorithms. No images are uploaded to any external server.
Common questions
Why is WebP format recommended?
WebP is a modern image format developed by Google that provides superior lossless and lossy compression for web images, typically yielding files 26% to 34% smaller than equivalent JPEGs.
What quality setting should I choose?
A quality setting of 75% to 80% is the industry sweet spot, stripping unnecessary EXIF data and applying imperceptible quantization that reduces file size dramatically without noticeable blur.
Will my images be stored on your servers?
Never. All compression and resizing occur entirely within your local device's graphics memory using HTML5 Canvas. Zero bytes are uploaded.
How does aspect ratio locking work?
When locked, changing the width automatically updates the height proportionately (and vice versa), preventing your images from becoming distorted or squished.