Generate Test Files for API Testing: The Privacy-Focused Browser-Based Solution
August 6, 2025
This browser-based tool generates mock files (images, videos, audio, documents) client-side for testing APIs, uploads, and storage, without server uploads.
The Backstory
I built this because I was tired of the hassle of finding and uploading real files for testing. It's such a time-waster! I knew there had to be a better way, something that respected user privacy and was super speedy. The client-side approach using Canvas and FFmpeg.wasm was the perfect solution – a true 'aha!' moment. The positive feedback (especially the comment about saving time!), well, that's just the cherry on top!
How to Play
Select your desired file type (video, image, audio, document).Specify the exact size and other parameters (duration for video, resolution for images).Click 'Generate' – your mock file appears instantly, ready for testing!
From The Community: Top Comments
For images and videos having broadcast/AV designed content would be great (color bars, focus patterns, etc)
I really like this, saving for later.
This is pretty cool
This could save a lot of time if it works well.. I really hate generating test assets. I really do.. Good one OP
The Remix Station
Think this toy has more potential? Vote for your favorite remix idea!
📺 Broadcast Mock-Up Master
Expand the video options to include broadcast-standard test patterns (color bars, test cards) for AV professionals.
0 Votes
🤖 Automated Testing Toolkit
Integrate an API allowing users to programmatically generate and download files, ideal for CI/CD pipelines.
0 Votes
Frequently Asked Questions
Can I use this tool for generating large files (e.g., 1GB videos) for testing?
The maximum size depends on your browser's capabilities and system resources. Experiment to find the limit.
Are the generated files truly functional or just placeholders?
They are completely functional. Videos play, audio sounds natural, and documents are readable – just like real files!