Dummy File Generator
DeveloperGenerate dummy files of any size for testing uploads and downloads. Create text, binary, or JSON test files.
File Settings
How it works
This tool generates a dummy file entirely in your browser's memory. It creates a Blob with random data of the specified size and triggers a download.
- Ideal for testing file upload limits
- Check download speeds locally
- Populate test directories
What is This Tool?
A dummy file generator creates test files of specified sizes for testing upload limits, download speeds, storage quotas, and file processing systems. Generate files from 1KB to 1GB+ in common formats (binary, text, CSV) with customizable content patterns.
Testing file operations requires files of specific sizes that are cumbersome to create manually. This tool generates files with configurable sizes (exact byte counts), content patterns (zeros, random, repeating), and formats — all created client-side without server uploads.
Common Use Cases
Upload Testing
Generate files at exact size limits to test upload validation, multipart handling, and file size restriction enforcement.
Network Testing
Create large files for testing download speeds, CDN performance, and network bandwidth measurement.
Storage Quota Testing
Fill storage to test quota enforcement, low-disk-space handling, and storage alerting in applications.
File Processing
Generate test files for validating file parsers, compression algorithms, and document processing pipelines.
Frequently Asked Questions
How large can files be?
Files are generated client-side, so maximum size depends on your browser's memory and disk space. Multi-GB files may require downloads in chunks.
What content is in generated files?
Options include null bytes (zeros), random data, repeating patterns, or structured text. Random data is not compressible; zeros compress to nearly nothing.
Are files generated locally?
Yes. Files are created entirely in your browser using Blob APIs. No data is uploaded to any server.