Complete calculator directory
All Calculators
Browse every completed LOT 894 calculator, converter and educational game. Each tool has clear inputs, focused results, practical explanations and supporting information.
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Open a focused calculator page for finance, mathematics, health, date planning, education, conversions or practice games. Calculations run directly in your browser.
FinanceSavings CalculatorEstimate how current savings and recurring deposits may grow with a stated APY.
FinanceCompound Interest CalculatorProject compound growth from a starting balance and regular monthly contributions.
FinanceRetirement Savings CalculatorProject retirement savings, compare a spending goal and estimate required contributions.
FinanceCredit Card Payoff CalculatorEstimate a credit card debt-free date, total interest, repayment and savings from an extra payment.
FinanceAPR CalculatorEstimate a fixed-rate loan APR, monthly payment, fee impact and total borrowing cost.
FinanceSalary Increase CalculatorCalculate a new gross salary and compare the increase across common pay periods.
FinanceSalary Payroll CalculatorEstimate gross pay, deductions, net pay, employer cost and payroll projections.
FinanceTip CalculatorCalculate a tip, final bill and equal amount per person.
HealthBMI CalculatorCalculate body mass index with age-appropriate interpretation for adults, children and teenagers.
HealthIdeal Weight CalculatorCompare established height-based reference formulas and a BMI-based healthy-weight range.
HealthPregnancy Due Date CalculatorEstimate a due date, pregnancy week, trimester and key timeline milestones.
Date & TimeAge CalculatorCalculate exact age, birthday progress, upcoming milestones and a detailed printable profile.
Date & TimeDate Difference CalculatorCalculate the exact calendar distance between two dates with holiday analysis and a printable report.
MathPercentage CalculatorSolve common percentage relationships with formulas, steps and a printable report.
MathPolynomial Root Finder CalculatorFind real and complex polynomial roots with steps, a graph and verification.
ConvertersPercentage Conversion CalculatorConvert fractions, decimals, percentages and ratios in five focused modes.
ConvertersUnit ConverterConvert everyday, engineering, digital, electrical, thermal and scientific measurements.
ConvertersCurrency Converter & Comparison CalculatorConvert currencies and compare provider rates, fees and final amounts received.
EducationGPA CalculatorCalculate a credit-weighted grade point average and review how each course affects the result.
EducationPeriodic Table & Chemistry CalculatorAnalyze elements, isotopes and ions with particle counts, electron shells and periodic-table position.
GamesAbacus QuestPractise place value and arithmetic with Soroban challenges and a learning report.
GamesMental Math RushPractise arithmetic speed and accuracy with adaptive rounds and a performance report.
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Use a focused collection when you already know the type of calculator you need.
Finance CalculatorsSavings, compound growth, retirement, credit, APR, salary, payroll and tipping tools.
Health CalculatorsBMI, ideal-weight and pregnancy timeline tools.
Date & Time CalculatorsAge, birthday milestones and calendar date differences.
Math CalculatorsPercentages and polynomial roots.
ConvertersNumber forms, measurement units and currencies.
Education CalculatorsGPA and chemistry reference tools.
GamesMental arithmetic and Soroban practice.