227 free calculators · every formula shown
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Loans, investments, tax, health and everyday maths, each with the formula shown and every result checked against an independent working.
- 227 calculators across 18 subjects
- 2,885 automated checks on every release
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227 calculators · 18 subjects
What do you want to work out today?
Try the loan estimator
Know the real cost of your loan before the bank tells you
What it really costs
Total interest over the life of the loan, worked out month by month.
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Every subject
- Time & DateTimestamps, timezones, durations, and date math.28 tools
- Finance & InvestmentSIP, compound interest, retirement, forecasting.86 tools
- Loans & DebtEMI, amortization, prepayment.17 tools
- Retirement PlanningReadiness, corpus, savings, drawdown, and age comparison.18 tools
- Salary & TaxTake-home pay, tax regimes, deductions.13 tools
- MathematicsBODMAS, scientific, statistics, fractions and ratios.32 tools
- Developer / ITBase conversion, encoding, hashing.7 tools
- NetworkingSubnets, latency, uptime, bitrates and data speeds.7 tools
- Data & StorageBytes, bits, decimal vs binary storage.5 tools
- EngineeringUnits, electrical, mechanical formulas.8 tools
- Health & FitnessBMI, BMR, TDEE, pace — estimates, not medical advice.22 tools
- BusinessMargins, markup, break-even.9 tools
- Unit ConvertersLength, mass, temperature, and more.18 tools
- Home & ConstructionArea, concrete, AC size, electricity and building materials.7 tools
- Travel & VehiclesFuel cost, mileage and vehicle maths.4 tools
- Science & WeatherPhysics, chemistry and weather formulas.7 tools
- EducationGPA, CGPA and grades.8 tools
- Other CalculatorsUseful tools that don't fit another section (yet).2 tools
Most used
Popular calculators
- Loans & DebtEMI PlannerCalculate your monthly EMI from loan amount, rate, and tenure.Open
- Finance & InvestmentSIP CalculatorProject the future value of a monthly SIP, with optional step-up.Open
- Retirement PlanningRetirement Readiness Planner"Am I on track to retire?" — the flagship retirement calculator.Open
- Salary & TaxIncome Tax Calculator (India) — Old vs New RegimeYour income tax for FY 2026-27 under both regimes — and which one saves more.Open
- Finance & InvestmentFD Calculator — Fixed Deposit Interest & MaturityMaturity value and interest on a fixed deposit — cumulative or monthly/quarterly payout, with TDS.Open
- Finance & InvestmentCompound Interest CalculatorSee how money grows with compounding, at any frequency.Open
- MathematicsPercentage CalculatorX% of Y, percentage change, what-percent-is-X-of-Y, percent error and percent difference.Open
- Health & FitnessBMI CalculatorBody Mass Index from your height and weight.Open
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227 tools across 18 subjects — free, private, and with the working shown.