Yes, radiometric dating is a very accurate way to date the Earth. We know it is accurate because radiometric dating is based on the radioactive decay of unstable isotopes. When an unstable Uranium (U) isotope decays, it turns into an isotope of the element Lead (Pb).
Why is radiometric dating wrong?
Radiometric dating is largely done on rock that has formed from solidified lava. Geologists assert that older dates are found deeper down in the geologic column, which they take as evidence that radiometric dating is giving true ages, since it is apparent that rocks that are deeper must be older.
How do we know how old fossil are?
To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.