Tree Age Calculator: Estimate Tree Lifespan Online

This tool calculates the approximate age of a tree based on its circumference.

Tree Age Calculator

Fill in the species of the tree and its circumference in inches. Optionally, you can also enter its height in feet to get a more accurate result. Click on the “Calculate” button to find out the approximate age of your tree.

How to Use the Calculator

  • Select the species of your tree from the dropdown menu.
  • Enter the circumference of the tree in inches.
  • Optionally, enter the height of the tree in feet.
  • Click “Calculate” to see the estimated age of the tree.

How it Works

The calculator uses a species-specific formula based on the circumference of the tree to estimate its age:

  • Oak: Age = Circumference * 0.4
  • Pine: Age = Circumference * 0.5
  • Maple: Age = Circumference * 0.3
  • Birch: Age = Circumference * 0.4
If the optional height is provided, the age will be adjusted based on the height. The final result is rounded to the nearest whole number and displayed as the tree’s approximate age in years.


This calculator provides an approximate age based on average growth rates for different tree species. Actual tree growth can be influenced by many factors including soil conditions, weather, water availability, and health of the tree. Therefore, the calculated age should be considered an estimate rather than an exact figure.

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