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Safe Withdrawal Rate Calculator
Enter your portfolio or target spending to see your year one withdrawal, the portfolio you need, and whether it's projected to last your retirement horizon.
July 14, 2026
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Every calculator on this page is completely free to use. No account, no sign-up, no strings. When you're ready to save your numbers and track them over time, Calm Sea is here.
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50/30/20 Budget Calculator
Enter your monthly take-home pay to see your recommended 50/30/20 budget split, then compare it against your actual spending on needs, wants, and savings.
July 8, 2026
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Rental Property Cashflow Calculator
Enter your rent, expenses, and mortgage to see monthly cashflow, NOI, cap rate, and cash-on-cash return — plus a year-by-year projection as rent and costs grow over time.
July 1, 2026
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Cash-on-Cash Return Calculator
Enter your down payment, closing costs, rent, and expenses to see your cash-on-cash return, find the rent needed to hit a target return, and see how CoC improves as rents grow.
June 30, 2026
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Gross Rent Multiplier Calculator
Screen investment properties in seconds. Calculate GRM from price and rent, estimate what a property should be worth, or find the rent a price implies — all from two inputs.
June 29, 2026
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Compound Interest Calculator
Enter your principal, annual rate, and time horizon to see how your asset grows. Add monthly contributions and choose a compounding frequency to model your savings or investment.
June 26, 2026
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LTV Calculator
Enter your property value and loan balance to see your Loan to Value Ratio (LTV), equity position, PMI status, and how your LTV changes as your property grows and your loan pays down.
June 25, 2026