The age of the earth is estimated to be
4.54 billion years old. And if we see the plus and minus then it is about
50 million years.

Overview
Determining the minerals and rocks of the different parts of the world one
can estimate the age of the earth with the help of carbon dating. Like in
northwestern Canada, scientists discovered the oldest Rock which is about 4.3 billion old. And in
Australia, they found minerals that are about 4.03 billion years.
The scientist knew the fact that the earth’s material is continuously changing its formation and hence they always vary the research place according to suitable specifications this is due to the Rock cycle of nature.
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It is believed that all the material which is being used in the research is related to the earth’s property and will be the same in age hence scientists use the Moon's sample
to check the age but, the result of the research was similar to the earth’s one
and both of them lies between 4.4 and 4.5 billion years.
Early calculation
The great physicist
Willian Thomson in 1862, and the first Boron Kelvin published a calculated age of the earth and said it is about
20 million to 400 million of age. Whereas the geologist were not ready to accept this intuition and a short span of earth.