Tree Age Calculator
Calculate the age of a tree using diameter at breast height and species growth factor
Calculate Tree Age
Select your tree species or choose "Custom Species" to enter a custom growth factor
Measure around the trunk at 4.5 feet (1.37 meters) above ground level
Tree Age Results
Formula used: Age = Growth Factor × Diameter at Breast Height (in inches)
Calculation: 0 years = 4.5 × 0.0"
Species: Red Maple (Growth Factor: 4.5)
Age Analysis
Example Calculation
Red Maple Tree Example
Tree Species: Red Maple
Growth Factor: 4.5
Circumference at breast height: 75 inches (6 feet 3 inches)
Diameter calculation: 75 ÷ π = 23.9 inches
Age Calculation
Age = Growth Factor × Diameter at Breast Height
Age = 4.5 × 23.9 inches
Age = 107.6 years (approximately 108 years old)
How to Measure Your Tree
Find Breast Height
Measure 4.5 feet (1.37m) above ground
Standard forestry measurement height
Measure Around
Wrap measuring tape around trunk
For circumference measurement
Calculate or Measure
Get diameter from circumference ÷ π
Or measure diameter directly
Growth Factor Guide
Fast Growing (2-3)
Cottonwood, Black Willow, Silver Maple
Medium Growing (4-5)
Red Maple, White Oak, Douglas Fir
Slow Growing (6-8)
American Beech, Dogwood, White Fir
Tip: The smaller the growth factor, the faster the tree grows!
Understanding Tree Age Calculation
How Does Tree Age Calculation Work?
Tree age estimation uses the relationship between a tree's diameter and its growth rate. By measuring the diameter at breast height (DBH) and multiplying by the species-specific growth factor, we can estimate how long the tree has been growing.
Why Measure at Breast Height?
- •Standard forestry measurement (4.5 feet above ground)
- •Avoids irregular trunk base and root flare
- •Provides consistent measurement point
- •Easy to reach and measure accurately
Formula Explanation
Age = Growth Factor × DBH (inches)
- Age: Estimated tree age in years
- Growth Factor: Species-specific growth rate constant
- DBH: Diameter at breast height in inches
Limitations
- • Growth rates vary with environmental conditions
- • Urban trees may grow differently than forest trees
- • Method provides estimates, not exact ages
- • Best accuracy achieved with species-specific factors