Why the same photo can weigh 3× less
Most JPGs were saved in a hurry — by a phone camera or an export button that plays it safe. MozJPEG, the encoder behind this page, spends more effort on every block of pixels and routinely cuts 40–70% of the size at 85% quality, a level indistinguishable from the original on photos. Email attachment limits, site upload caps and slow uploads all stop being a problem.
Compression runs entirely in your browser — the photos never leave your device, so it's safe for documents, IDs and client work. Drop a whole folder: each file downloads automatically as it finishes.
Frequently asked questions
What quality should I pick?
85% is the sweet spot for photos — visually identical, much smaller. Go down to 70–75% for web thumbnails where every kilobyte counts, and up to 92–95% for print.
Does it resize my image?
No — the pixel dimensions stay exactly the same, only the encoding gets smarter. If you also need smaller dimensions, run it through Image Resize first.
Why is this better than my computer's "export as JPG"?
Built-in exporters optimize for speed. MozJPEG optimizes for size: trellis quantization and better Huffman tables squeeze out bytes that standard encoders leave on the table.