Simple Tools for Investors
Essential private financial calculators for retail investors, real estate planners, and savers. Calculate compound growth with visual charts, inflation adjustments, and percentage returns without sharing sensitive financial data.
Featured Investment Calculators
Direct access to our most popular fast, client-side financial tools.
Calculate investment growth with visual charts, inflation, and compounding
Calculate compound annual growth rate of any investment
Estimate monthly payments, total interest, and loan cost
Calculate percentages, increases, and decreases instantly
Work out sale prices, savings, and discount percentages
A clean, simple standard calculator with history and keyboard support.
1. Compound Growth
Project how your monthly savings and dividend reinvestments grow over 5, 10, 20, or 30 years with compounding interest.
2. Loan Amortisation
Break down mortgage and loan schedules to see exactly how much goes toward principal versus interest each month.
3. 100% Private
Zero cloud sync. Your account balances, salary numbers, and investment plans never leave your device.
Frequently Asked Questions
Why use browser-based investment tools over spreadsheets or online accounts?
Simply Tools calculators run 100% locally in your browser memory without account signups, subscriptions, or cookies tracking your financial calculations. Your net worth, investment principal, interest rates, and loan balances remain completely confidential.
How does compound interest accelerate portfolio growth?
Compound interest earns interest on your previous interest earnings in addition to your initial principal. Regular monthly contributions compounded over 10 to 30 years dramatically amplify investment returns compared to simple linear interest.
Can I calculate both stock returns and real estate mortgage payments?
Yes. Use the Compound Interest Calculator for index funds and stock portfolios, the Loan Calculator for fixed-rate mortgage amortisation and interest costs, and the Percentage Calculator for tracking portfolio percentage gains and dividend yields.
Are my portfolio numbers or calculations stored anywhere?
No. Everything is calculated in real-time in your browser JavaScript runtime. No financial data is ever sent to our servers or stored in any remote database.
Ready to calculate your investment growth?
Start with our free Compound Interest Calculator to simulate long-term portfolio returns with zero registration.