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Calculators & Modeling Tools 
The links below provide access to several easy-to-use calculators and more sophisticated modeling tools to assess the effectiveness of mobile source-based control strategies. State and local agencies can use these calculators and tools to estimate emission reductions or to conduct an analyses of the outcome that a specific emission-reduction strategy may produce.
Modeling Tools
- Modeling and Inventories
Access EPA's MOBILE Model, NONROAD Model, and various Fuel Models and Inventories. These models are methods used by EPA to estimate emissions from on-road vehicles, nonroad sources, and fuels. Inventories are calculations of total emissions of a pollutant for a given area at a defined time and set of conditions.
Calculators
Run these calculators for estimates of emission reductions and fuel impacts associated with a particular transportation-related strategy:
- Airport Ground Support Equipment (GSE) Model
A spreadsheet tool that provides users with a quick analysis of the emission benefits and cost-effectiveness of controling GSE emissions. - Business Benefits Calculator
Use this tool to estimate the financial, environmental, traffic, parking, and related values of offering employees high quality commuter benefits. - COMMUTER Model
Calculate transportation and emissions benefits associated with selected commuter benefits, incentives, and other voluntary strategies to reduce solo commuting. Emission reductions for VOCs, NOx, CO, air toxics, and CO2 may be calculated. - SmartWay FLEET Performance Model
Conduct a thorough assessment of the environmental performance of fleet (truck) operations, and calculate additional fuel savings and emission reductions (CO2, NOx, and PM) that can be achieved through a range of options and strategies. - SmartWay Technology Package Savings Calculator
Use this easy-to-use calculator for a quick comparison of costs, fuel savings, and emission benefits associated with various truck and engine technologies (single truck and fleet operations). - Retrofit Calculator
Characterize a truck or bus fleet and calculate the tons of emission reductions (CO, CO2, NOx, hydrocarbons, and PM) that a retrofit project will generate. - School Bus Calculator
Calculate fuel savings that can be generated by reducing the amount of time school buses idle.