Your files stay in your browser

HappyCSV tools are designed for local, client-side processing. The selected file is read by your browser and the result is generated on your device; the source file is not uploaded to HappyCSV.

Browser memory and device capacity still matter. Individual files are limited to 100MB, and a warning is shown for larger jobs that may be demanding for a device.

Third-party services are limited to site analytics and do not receive the file contents processed by the tools. Do not use a tool for regulated data unless your own privacy and compliance review approves the workflow.

We welcome responsible reports about security issues. Please include the affected page, a minimal reproduction, and the impact in a private issue or discussion in the project repository.