How to use the i-Tree Harvest Carbon Calculator:


Forest carbon is stored in harvested wood products. However many forest carbon calculators do not include a harvested wood products category, and estimating the amount of carbon in this pool can be cumbersome. i-Tree Harvest – formerly PRESTO (PRoduct EStimation Tool Online) - lets users estimate the carbon stored in harvested wood products and the changes in this quantity over time, using some basic details about a harvest. Users need to register to use the tool, however registration is free.

The i-Tree Harvest Carbon Calculator provides general carbon storage estimates for wood products based on geographic region, wood type, and harvest volume.

User Guide

Complete User Guide (pdf): How to use PRESTO

NOTE: this PDF is for the earlier ESSA-based version of the PRESTO tool and there will be some differences.


Registering and logging in is not required for this tool. Geography: Conterminous United States Scale (range): Forest Stand Training Requirement: 1 (on a scale of 1-3). Minimal time investment (<2 hours).

Overview & Applicability

Inputs and Outputs

Inputs include a few basic measurements about the harvested stand, including:

Outputs include several calculated carbon estimates expressed in tonnes per hectare. Calculated values include total carbon storage after 100 years (C100) and average annual carbon storage (CAvg) for:

A 10 Year Report is also produced, which shows carbon storage calculations in 10-year increments, so you can see how carbon storage changes over time for each of the five storage categories. All calculations can be exported to Excel.

Restrictions and Limitations

Please note that the carbon ratios that i-Tree Harvest Carbon Calculator uses were developed as general ratios for each region, compiled from available data. Species-specific ratios were not developed as the available data sets would be too small to produce values that could be widely applied. As with any calculator, the results are only as good as the data entered – the tool will not flag or correct extreme values that have been entered mistakenly.