Worthless. It should be financialcalculator.com to be grammatically correct and memorable. But even that suffers from having too many letters and lacking branding potential.
Both domains look clean and niche-friendly. Automated valuations aren’t always accurate, so real value depends on demand and end-user interest. I’ve worked with tools like the (ti 84 calculator), and keyword-based names like yours can perform well when developed properly. Good luck with the sale!