Sized File Generator
Generate a dummy file of an exact size, for testing uploads or storage limits, entirely in your browser.
About this tool
Pick a size and unit, choose whether the bytes should all be zero or random, and download a file built to that exact size — handy for testing an upload form's size limit, checking how your site or app behaves near a storage quota, or seeing how a slow connection copes with a big transfer. Sizes here use binary units (1 KB = 1,024 bytes, 1 MB = 1,024 KB, 1 GB = 1,024 MB), the same convention your operating system usually uses for file sizes — some other tools use 1,000-based units instead, which gives slightly smaller numbers for the same nominal size. To avoid freezing or crashing the browser tab, requested sizes are capped at 2 GB; anything larger is rejected with a clear message rather than left to hang. Nothing is uploaded anywhere — the file is built and downloaded entirely on your device.