Pick a folder and Diskmap adds up everything inside it, then shows the biggest subfolders and files as sorted bars you can drill into — a private, in-browser way to find what's filling your disk. It only reads sizes; nothing is opened, moved or changed, and nothing is uploaded.

Chrome or Edge only. This tool uses the File System Access API to read a folder you pick. Firefox and Safari don't support it yet — open this page in Chrome or Edge.

Sizes are logical file sizes summed recursively; your operating system may report slightly different totals because of block allocation and compression. Symlinks and files the browser can't open are skipped. The whole tree is read once into memory, so extremely large folders (hundreds of thousands of files) may take a moment. Everything runs on your device.