NumSysConverter 1.0 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. This Mac application was originally designed by Romanysoft LAB. NumSysConverter for Mac lies within System Tools, more precisely Automation.
From the developer:
NumSysConverter is specifically designed to handle digital conversion. The application supports binary conversion. All you need to do is determine the source number system and the destination number system, enter the number you need to convert, and enable the conversion.
You may want to check out more Mac applications, such as iPAD, which might be related to NumSysConverter.