Practical guidance
Back up source files and check web server requirements first. Changing formats does not extend certificate validity or fix domain names. Never submit private keys to unknown online converters.
Before using this tool
Define what you need from Certificate format converter and prepare the relevant input. When diagnosing a live service, record the test time and connection conditions so you can compare results after configuration changes. Check findings against the documentation for your software.
Tool availability
This is currently an information page. No working form, calculations or submission to diagnostic services is available yet. The interface and supported input formats will be documented when functionality is released.