About Random File Generator
A test file of a known size is useful for checking upload limits, measuring transfer speed, and testing how software handles large inputs. Random bytes come from the cryptographic generator in your browser and do not compress, which matters when a link or archive applies compression. Zeros and repeating text compress almost completely. Sizes use binary units, where 1 MB is 1,048,576 bytes. The file is built in memory, so the limit here is 1 GB.
How to use Random File Generator
- Enter the file size and choose the unit: bytes, KB, MB, or GB.
- Choose what fills the file: random bytes, zeros, or repeating text.
- Type a file name with the extension you need.
- Press "Create and download" to save the file.
Questions about Random File Generator
Why does a file of zeros upload faster than a random file?
Many servers, VPNs, and transfer tools compress data in transit. A file of zeros shrinks to almost nothing, so less is sent. Random data cannot be compressed, which makes it the honest choice for speed tests.
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