Calculation Methodology

Formula selection

We use standard, widely-accepted formulas, shown on each tool page.

Assumptions (such as compounding frequency) are stated, and results are rounded for readability while keeping full precision internally.

Tools support metric/imperial units and multiple currencies, formatted to your selection.

Each tool has test cases for normal, edge and error inputs. Results are estimates and should be verified for important decisions.

To report a calculation issue, email needme7760@gmail.com and include the tool name, your inputs and the expected result.