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Smart money math, made simple

Free calculators for the money decisions that matter — from mortgages and retirement to freelancer taxes. No signup, no data collection: everything runs in your browser.

✓ Always free✓ 2026 IRS figures✓ Nothing you type leaves your browser
Ad space — 728×90 leaderboard
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Mortgage Calculator

Monthly payment with taxes, insurance & HOA — plus a full amortization schedule.

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Loan Calculator

Car, personal or student loan payments and the true total cost of borrowing.

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Compound Interest Calculator

Watch deposits plus monthly contributions snowball over the years.

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Retirement Calculator

Project your nest egg and the monthly income it could sustain.

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Savings Goal Calculator

The exact monthly amount to hit any savings target on time.

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Salary to Hourly Calculator

Convert annual salary to hourly, daily, weekly and biweekly pay.

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Self-Employment Tax Calculator

2026 SE tax for freelancers: Social Security + Medicare, done right.

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Quarterly Tax Calculator

What to send the IRS each quarter — with deadlines and reminders.

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Freelance Rate Calculator

Work backwards from your target income to the rate you should charge.

Built for real decisions

Every PiggyMath calculator uses the standard formulas taught in finance — the same amortization and compound-interest math used by banks and lenders — and our tax tools are updated with the official 2026 IRS figures: current brackets, the $16,100/$32,200 standard deduction, and the $184,500 Social Security wage base. Drag the sliders, watch the charts move, and get answers in seconds.