QUICK ANSWERStart with the tool that matches your immediate input.
Open Overtime Cost Calculator first when its stated purpose matches the result you need now. Use Project Profitability Calculator only when it solves a separate next task.
This guide is for founders, freelancers, marketers, sellers, and small teams. Start with Overtime Cost Calculator when your immediate task is to model overtime cost with visible assumptions and decision-ready metrics. Move to Project Profitability Calculator only when you also need to model project profitability with visible assumptions and decision-ready metrics.
The goal is not to run two tools automatically. It is to finish the first narrow task, inspect its result, and then decide whether Project Profitability Calculator solves a genuinely different next step.
Both tools sit in Business & Marketing, but they handle different inputs or outcomes. Keeping those roles separate reduces repeated work and makes verification easier.