About DupFind

dupfind finds duplicate and near-duplicate photos in a folder you choose. It hashes every image in your browser using two perceptual fingerprints, so resized, re-saved and messaged copies are caught, not just byte-identical files. Nothing is deleted until you say so and nothing is uploaded; the hashing runs in web workers on your own processor. I wrote it while sorting a parent's photo library of forty thousand pictures.

Who

DupFind is built and looked after by Saurav Kumar Sharma, an independent developer in India. There is no company behind it and no team; if something breaks, the person who fixes it is the person who wrote it.

How it is built

Everything on this site runs inside your browser. Files you open stay on your device; there is no upload step and no server that could keep a copy. Once loaded, the tool keeps working without a connection. The core engine is my own code rather than a wrapped third-party service, which is why the site can promise that nothing leaves your machine. Drafts of the written guides are prepared with software help and then edited by hand; the measurements and examples come from running the tool.

Contact

Questions or a bug report: hello@dupfind.com. One person reads it; replies take a day or two.

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