Ballpark Math

Ballpark Math is a calculator for real-world decisions where exact numbers are unknown. Instead of punching in a single made-up figure, you can input ranges like "$18k to $26k" to see the resulting middle ground and uncertainty width. The tool features unit-aware calculations, sensitivity analysis to identify which variables impact your range the most, and a collection of worked examples for house affordability, renovations, and side projects. Files are stored as plain text locally on your device.