Interest Calculators
All interest tools in one place: compound interest with monthly contributions, simple interest, APR, investment growth, savings goals and inflation.
7 tools with distinct tasks. Global tools use your entered assumptions; US and UK tools state their local scope and rule year.
Simple interest applies to the original principal. Compound projections reinvest returns, while APR estimates a loan’s fee-adjusted rate. A hypothetical savings return is not a guaranteed rate.
Compound Interest Calculator
Project a future balance from an initial investment, monthly contributions and an assumed interest rate. Compare compounding frequencies and separate your deposits from interest earned.
↗LoansSimple Interest Calculator
Calculate interest charged only on the original principal, using a chosen annual rate and time period.
↗LoansAPR Calculator
Estimate a fee-adjusted annual loan rate from net funds received and equal monthly repayments.
↗SavingsInvestment Growth Calculator
Model investment contributions that rise or fall each year, and compare constant-return scenarios.
↗SavingsSavings Goal Calculator
Find the monthly saving needed to reach your target.
↗PlanningInflation Calculator
Compare a future equivalent price with the purchasing power of an unchanged cash amount under your chosen inflation rate.
↗UK · Investment & Savings TaxSavings Interest Tax Calculator
Estimate ordinary savings-interest tax in a supported England, Wales or Northern Ireland scenario. Show the direct interest tax and any wider allowance-taper effect.
↗Related collections
Mortgage Calculators for the US and UK
Browse all calculators or read our calculation methodology.