Interest Calculator

Calculate interest earned or paid on any amount β€” supports both simple and compound interest with flexible compounding options.

Total Interest (Compound)

$2,834

Total Amount

$12,834

Effective Rate

5.116%

How to Calculate Interest

This calculator supports both simple interest (I = P Γ— r Γ— t) and compound interest (A = P Γ— (1 + r/n)nt).

Types of Interest

  • Simple β€” charged on principal only
  • Compound β€” charged on principal + accumulated interest

How Banks Calculate Interest

US banks use the daily balance method: interest calculated daily, summed at month-end.

Interest Rate Environment

The Federal Reserve's funds rate influences all consumer rates. Higher Fed rates = better savings APYs but costlier loans.

Interest Calculator FAQ