The age of the Earth is important to know, and we can calculate the age by using the Bible. Generally speaking, from Adam to Abraham, there was a time span of about 2,000 years. From Abraham to Jesus, there was another 2,000 years. Finally, from Jesus’ birth to the present, we have another 2,000 years. Adding all of these times together equals to 6,000 years of Earth history (granted, this is not the exact age).
We know that there were 7 literal days during the week of Creation. If we count the genealogies in Genesis Chapters 5 and 11 along with other historical events from the Old Testament, we can calculate the age of the Earth to be between 6,000 and 10,000 years old. There are some discrepancies with ages based on different manuscripts, thus there is a 4,000 year range between the estimated age of the earth, but none of these discrepancies would ever allow for the age to be hundreds of thousands or millions of years old. Please see the following article for more information: “What are the problems with believing in millions of years?”