QUICK ANSWERStart with the tool that matches your immediate input.
Open Smoking Cost Calculator first when its stated purpose matches the result you need now. Use VO2 Max Estimator only when it solves a separate next task.
This guide is for people using general educational wellness and planning tools. Start with Smoking Cost Calculator when your immediate task is to use the Smoking Cost Calculator to calculate a transparent estimate and understand the next step. Move to VO2 Max Estimator only when you also need to use the VO2 Max Estimator to calculate a transparent estimate and understand the next step.
The goal is not to run two tools automatically. It is to finish the first narrow task, inspect its result, and then decide whether VO2 Max Estimator solves a genuinely different next step.
Both tools sit in Health & Wellness, but they handle different inputs or outcomes. Keeping those roles separate reduces repeated work and makes verification easier.