I'm currently working on a physics project for school, and I'm having trouble calculating mass due to unit conversions and density differences. Can anyone recommend simple methods or tools for accurate and quick calculations?

Last week, I was helping my nephew with a project for school—we needed to calculate the mass of a plaster cast to see if the stand would support it. I remembered the physics formula, but as luck would have it, I started getting confused about densities and the transitions between units. To avoid making mistakes, I decided to look for a handy tool and came across a mass calculator https://calculatorcore.com/converters/mass-calculator/ . It quickly calculated everything and saved me a lot of headaches.