Smart Image Optimizer (No Visible Loss)
Finds the smallest file that still looks identical to your original, measured with SSIM instead of guessing a quality number. Free, private and instant: it runs entirely in your browser.
- Processed locally
- No upload, no wait
- No sign-up
- No watermark
Drop images here
or choose files · paste with Ctrl/⌘ V
JPG, PNG, WebP, HEIC, AVIF, GIF, TIFF, SVG, RAW, PSD, JXL, BMP, ICO and more
How to use Smart Optimizer
- 1
Drop your images, choose files, or paste from the clipboard.
- 2
Adjust the options.
- 3
Click Optimize. Files are processed on your device.
- 4
Download each result or everything as a ZIP.
Why use Aback Images for smart optimizer
Processed on your device
Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.
Instant results
Everything runs locally in a background thread, so there is no upload queue and no waiting on a server.
Batch friendly
Process many images at once and download them individually or as a ZIP.
Every format
Works with JPG, PNG, WebP, AVIF, HEIC, GIF, TIFF, SVG, RAW and more, identified by content rather than file name.
Related tools
Shrink JPG, PNG, WebP, AVIF and GIF files with MozJPEG, OxiPNG and modern codecs, with a live before/after preview.
Make JPEG photos smaller with MozJPEG, the encoder that beats standard JPEG by 10-15% at the same quality.
Cut PNG size by up to 80% with smart palette reduction and OxiPNG lossless optimisation, keeping transparency.
Re-encode WebP images smaller with libwebp's best settings, including animated WebP.
Shrink animated GIFs by reducing colours, dropping frames and resizing, while keeping the animation.
Hit a file-size limit for forms and uploads. Searches quality, then dimensions, and can pad up to a minimum.
Encodes your image as JPG, WebP and AVIF at the same visual quality and keeps the smallest one.
Make images website-ready in one pass: WebP at quality 78, at most 1920 px on the long side, camera metadata removed.
Guides
Lossy vs lossless compression: how to shrink images without visible loss
What each kind of compression throws away, which formats use which, and a practical routine for making images smaller without anyone noticing.
2 min read
How to compress an image without uploading it
Make photos and graphics smaller in your browser: which preset to pick, why resizing often saves more than quality, and what compression cannot fix.
3 min read
Frequently asked questions
Are my images uploaded anywhere?
No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.
Can I process many files at once?
Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.
Is it free? Is there a file limit or watermark?
It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.