Random File Generator
Generate dummy PDF or DOCX files for testing uploads and storage.
Configuration
Ready to Generate
Small PDF file with lorem content.
About the Random File Generator
Sometimes you need a file of a specific size — to test a file-upload limit, exercise an S3 multi-part flow, or simulate a slow download in your QA environment. Hand-crafting one with dd is doable but inconvenient when you only need a few. This generator produces files of arbitrary size, filled with random or repeating content, with a single click and downloads them straight to your machine.
File generation happens in the browser using the FileSystem and Blob APIs. The bytes are never sent over the network, which means you can produce gigabyte-class files without consuming any bandwidth.
How to use
- Pick the file size — bytes, kilobytes, megabytes or gigabytes (subject to browser memory).
- Choose the content: random bytes, ASCII text, all zeros, or a repeating pattern.
- Set the file extension and click Generate.
- The file downloads automatically.
Common use cases
- Testing the maximum upload size enforced by a backend.
- Generating sample binaries for backup-and-restore drills.
- Producing dummy logs for performance testing of log aggregators.
- Filling a disk to test full-disk error handling.
Frequently asked questions
How large can the file be?
The browser will refuse to allocate Blobs larger than its address space allows. In practice files up to ~2GB work in modern Chromium and Firefox; larger files may need a streaming approach.
Is the random content cryptographically random?
It uses crypto.getRandomValues() so the output is suitable for entropy testing, but it is wasteful to generate huge cryptographic randoms — pick "pattern" mode if you only need a placeholder.
Advertisement