Random File Generator
Make test files of an exact size in seconds. Random bytes, zeros or text, or real PNG, PDF, ZIP, DOCX and MP4 files that open in their own apps. Up to 10,000 at once, every one different, with a free-space check before anything is written.
Every card is one file. Click the hopper and watch them punch.
See it in action
About Random File Generator
Need 12 PDFs of exactly 25 MB to test an upload limit? Random File Generator makes them in seconds.
Real files, not just noise
Pick what goes inside. Random bytes, zeros and text are there as before, and now you can make real PNG, PDF, ZIP, DOCX and MP4 files. Each one opens in its own app: the PNG is a picture of static in Photos, the PDF a one-page document, the ZIP an archive File Explorer can open, the DOCX a document Word opens, and the MP4 a short test clip that plays. The rest of the file is padded to the exact size you asked for.
Exactly the size you asked for
Set how many files and how big each one is, in bytes, KB, MB or GB. Make up to 10,000 at once. A valid file needs a little room of its own: a PNG at least 84 bytes, an MP4 about 13 KB. ZIP and DOCX files go up to 4 GB.
No two files alike
Every file gets its own fresh random content, so no two files are identical, and random bytes use the full range from 0 to 255. Zero-filled files are sparse where the drive allows it, so a big test file takes almost no room.
Checks the room first
The window shows what the set adds up to and how much the drive has free. A set that will not fit is never started.
Watch it work
Every file is a punched card in the hopper. Click the hopper to start and watch the cards punch and feed. Click it again to stop: the file being written is deleted, and finished files are kept. Existing files are never overwritten, because numbering carries on after the files already in the folder.
Your way
Choose how file names start, and have the folder open when a set is finished. Your file count and size from the earlier version carry over. Light and dark themes, or match Windows.
Features
- Make up to 10,000 test files at once, each exactly the size you ask for, in bytes, KB, MB or GB
- Eight kinds of content: random bytes, zeros, text, or real PNG, PDF, ZIP, DOCX and MP4 files
- The PNG, PDF, ZIP, DOCX and MP4 files are real files that open in Photos, a PDF reader, File Explorer, Word and Media Player
- Every file gets its own fresh random content, so no two files are ever identical
- Random bytes use the full range from 0 to 255
- Zero-filled files are sparse where the drive allows it, so they take almost no room
- Shows how much room the set needs and how much the drive has free, and will not start a set that does not fit
- Watch the progress on the card hopper, and stop at any time. The file being written is deleted, finished files are kept
- Existing files are never overwritten: numbering carries on after the files already in the folder
- Choose how file names start, like test_001.pdf
- Open the folder automatically when a set is finished
- Your file count and size from the earlier version carry over
- Light and dark themes, or match Windows
Details
- Works on
- Windows 10 (1809 or later) and Windows 11
- Download
- About 2.8 MB
- Version
- 2.0.2, updated October 2026
- First released
- December 2022
- Price
- $1.99 once. No subscription.
- Category
- Developer tools
What's new in 2.0.2
- New: make real PNG, PDF, ZIP, DOCX and MP4 files that open in their own apps
- New: zeros and text, alongside random bytes
- New: every file is exactly the size you ask for, and no two are alike
- New: a free-space check before anything is written
- New: watch progress and stop at any time. A half-written file is never left behind
- Fixed: files are named test_001.bin rather than file.bin_0.bin, and existing files are never overwritten
- Fixed: errors are now reported instead of being silently ignored
- Your file count and size carry over
Questions
Anything else? Ask us
Which versions of Windows does it run on?
Windows 10 (version 1809 or later) and Windows 11.
Is it a subscription?
No. Random File Generator is a one-time purchase of $1.99, and updates are included.
How do I get it?
EvlarSoft apps are moving to direct downloads from this site. Ask to be notified and we will email you as soon as Random File Generator is ready to download.
