Frequently asked questions

No. Every step — reading the file, resizing, compressing, zipping — happens locally in your browser. Nothing is ever sent to a server. See the Privacy Policy for the full explanation.

Instead of picking a quality percentage and hoping, you type in a size like "500 KB" and Quantize automatically tests different compression levels until it finds one that lands at or just under that size. It's the same manual trial-and-error you'd otherwise do by hand, just automated.

PNG is a lossless format — it doesn't have a quality setting to adjust, so there's no compression level to search through. For PNG, file size depends mainly on the image's resolution and complexity. If you need a specific file size with PNG-like quality, try WebP instead, which supports both lossless and lossy modes at a much smaller size.

JPG is the most universally compatible and compresses photos well, but doesn't support transparency. PNG is lossless and supports transparency, but produces larger files for photos. WebP usually gives the smallest file size for a given quality level and supports transparency, but very old software occasionally doesn't support it.

If set, any image wider than that value gets scaled down proportionally before compression. This is often the single biggest lever for reducing file size — a smaller image compresses to a much smaller file than a large one, even at the same quality setting.

No hard limit, but very large batches or very large individual photos will take longer since everything is processed on your device rather than a server. If your browser feels sluggish with a big batch, try processing in smaller groups.

Yes — every processed image has its own "Download" button in the file list, in addition to the "Download all" zip option.

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