Interest Calculators

Calculate compound interest with detailed year-by-year breakdown, interactive growth charts, and comprehensive investment analysis including effective annual rate and growth projections.

Calculate continuous compounding interest and future value with step-by-step formulas, growth visualization, and comparison charts. Understand the power of Euler's number (e) in financial calculations.

Calculate how long it takes for an investment or value to double at a constant growth rate. Features Rule of 72 comparison, multiple growth milestones, and interactive visualizations.

Use the Rule of 72 to instantly estimate how long it takes to double your investment at a given interest rate. Features interactive timeline visualization, comparison of approximation rules, and growth projections.

Enter principal, annual rate and a duration in days, weeks, months or years. Calculate simple interest and the total principal plus interest.