Dummy Excel Generator Online
Generate dummy Excel (.xlsx) files of any file size instantly in your browser. Perfect for testing file upload limits, storage quotas, and Excel import pipelines — no server, no upload required.
Frequently Asked Questions about Dummy Excel Generator
How do I generate a dummy Excel file of a specific file size?
Enter your desired file size in MB or KB, then click Generate & Download. The .xlsx file is created entirely in your browser using the jszip library and downloaded immediately — no server is involved.
Is the generated file a valid Excel file?
Yes. The generated file is a valid .xlsx (Office Open XML) file that can be opened in Microsoft Excel, LibreOffice, Google Sheets, and any other spreadsheet application that supports the .xlsx format.
Why do developers need dummy Excel files by file size?
Dummy Excel files are used to test file upload size limits on servers and APIs, simulate large imports in ETL pipelines, verify file size validation logic, and stress-test Excel parsing performance with large files.
How accurate is the generated file size?
The file size is exact. The tool creates a valid .xlsx structure and adds a padding file using ZIP STORE (no compression) to hit the target size precisely. The actual downloaded file will be within a few bytes of the requested size.
What is the maximum file size I can generate?
There is no hard limit in the tool, but your browser's available memory sets the practical limit. Files up to 200MB typically work fine on modern devices. Very large files (500MB+) may cause slowness depending on available RAM.
Is this tool free and private?
Yes, completely free. All file generation happens 100% inside your browser. No files are uploaded to any server. Your data and generated files stay entirely on your device.
Can I use the generated file to test API file upload limits?
Yes. Generate a file just above your server's upload limit (e.g., 10.1MB for a 10MB limit) to verify your validation logic correctly rejects oversized uploads.