Tree Age Calculator

Estimate a living tree's age from its diameter.

Estimated age (years) 90

Formula: age = diameter × growth factor

Step-by-step with your numbers:

1. Values used:

2. Diameter (DBH) = 20

3. Species growth factor = 4.5

5. Estimated age = Diameter (DBH) x Species growth factor = 20 x 4.5 = 90years

Did we solve your problem today?

Estimate a tree's age without coring, using a species growth factor.

The math behind it

age ≈ DBH (in) × growth factor. Factors: oak ~5, maple ~4.5, pine ~3.5, redwood ~7.

20 in oak (factor 4.5) → ~90 years.

How accurate?

A rough estimate — growth varies with climate, soil and crowding.