Contact and bug reports
Tell GreatJIN about incorrect calculations, bugs, unclear explanations or feature ideas.
How to get in touch
Operator: GreatJIN
Email: greatjin@greatjin.com
LinkedIn profile
The email link opens your device's mail app. If it does not open, copy the address into your usual email service. This page has no upload or contact collection form.
Information that helps reproduce a bug
- The tool URL and whether you used Korean or English
- Browser name, device type and the steps leading to the problem
- A short input example with sensitive details removed, and your selected options
- Expected and actual results, plus a screenshot with personal details hidden if possible
For example, include the input and output for an MB-to-MiB conversion, or whether the base date was included in a date calculation.
Personal information and sensitive files
Do not send passwords, API keys, authentication codes, national ID numbers or private original documents. Use the same email address for privacy questions or requests to delete an email you sent.
Responses and changes
This independently operated service cannot guarantee an immediate response or a specific turnaround time. Reports and suggestions are reviewed with reproducibility and the scope of the tools in mind.