The objective of this study was to develop an interactive cow cooling investment decision support tool for dairy farms in low and high humidity regions, and to demonstrate the economic benefits of investing in cow cooling. The low humidity region in the study was specific to semi-arid areas of sub-Saharan Africa (e.g., Malawi and Zambia) with THI range of 68 to 72. The high humidity region represented countries in the temperate regions with a climate distinctly different from that of sub-Saharan Africa in terms of humidity and temperature. The user inputs included total herd size, lactating herd size, milk yield, feed required per kg of added milk, feed price per ton, and milk price. Cow cooling inputs included fan and soaker costs, water and electricity cost, annual number of days cooling system was used, annual interest rate, discount rate, tax rate, predicted daily increase in milk production due to cooling and predicted yearly increase in pregnancy rate for the herd. The investment analysis outputs included net present value (NPV) and benefit: cost ratio (BCR). Assumptions used in calculating NPV and BCR included economic benefits of reduced heat stress extend to periods of low heat stress, no cooling existed, fans installed in stalls and holding area, and soakers installed in feed line and exit area from parlor. The assumptions were sourced from published literature and actual market prices of farm inputs and utilities. Using a herd size of 100 cows and a 10-year investment horizon, cow cooling in a high humidity region had a greater NPV ($54,653) compared with a low humidity region ($26,520). This could be attributed to high operating and initial investment cost for low humidity region. The BCR was greater than 1 for all the regions, indicating a good investment scenario. Further studies should be conducted to compare the current cow cooling investment analysis and other heat abatement strategies such as feed adjustment for small herd sizes in low humidity regions and semi-arid environments.