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Calcimator

Tree Age Estimator

Estimate a tree's age from its diameter at breast height (DBH) and species growth factor without coring.

Inputs

inches

Results

Estimated Age

90 years

Age Range (low)77 years
Age Range (high)103 years
SpeciesOak
Growth Rate0.2 in/year
Circumference56.5 inches
Estimated Height55 ft
CO₂ Stored378 lbs
Historical ContextEstablished ~1936
How to Use This Calculator
  1. Enter the Diameter at Breast Height (DBH) in inches measured at 4.5 feet above ground.
  2. Select the Species to apply the correct growth factor for your tree type.
  3. Review Estimated Age and the Age Range (low/high) to account for growth rate variability.
  4. Check CO₂ Stored in pounds to quantify the individual tree's carbon contribution.
  5. Use Historical Context to relate the tree's age to significant events in the area's history.

How the result changes with Diameter at Breast Height

Diameter at Breast HeightEstimated Age
8.945 years
29145 years
52260 years
72360 years

What each input means

Diameter at Breast Height
Tree diameter measured at 4.5 feet above ground. Measure circumference and divide by 3.14.
Species
Tree species: 1 = Oak (5.0), 2 = Maple (4.5), 3 = Pine (3.5), 4 = Spruce (4.0), 5 = Birch (5.0). Factor = years per inch of DBH.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    Diameter at Breast Height = 18, Species = 1 = 2 input(s) provided
  2. Calculate Estimated Age
    Estimated Age
    90 = 90
  3. Calculate Age Range
    Age Range
    77 = 77
  4. Calculate Age Range
    Age Range
    103 = 103

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