Interest Calculator

Calculate simple interest, compound interest and equal-installment payments, with multiple repayment options to compare.

Formulas

  • Simple Interest: Interest = Principal × Rate × Term
  • Compound Interest: Total = Principal × (1 + Rate/n)^(n×Term), where n is the compounding frequency
  • Equal Payment: Monthly Payment = Principal × Monthly Rate × (1+Monthly Rate)^Periods / ((1+Monthly Rate)^Periods - 1)
  • Equal Principal: Monthly Payment = Principal/Periods + Remaining Principal × Monthly Rate (decreasing monthly)

Usage Instructions

Features

The interest calculator supports three calculation modes — simple interest, compound interest and loan (equal payment / equal principal) — helping you quickly understand interest and repayment scenarios.

Steps

Select a calculation type (Simple / Compound / Loan) → Enter parameters such as principal, rate and term → View interest, total and other results in real time.

Notes

Rate is entered as a percentage (e.g. 5 means 5%); all calculations run locally in the browser and results are for reference only.