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All calculators
Search or browse the complete ArithPilot calculator library. Each tool includes instant results, formulas, worked examples, limitations, and links to related terms so you can check the assumptions behind the answer.
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Find the calculator by the job you need to finish
If you are not sure which page to open first, start with the task closest to your question. Finance tools are best for comparison and budgeting, health tools are broad estimates, math tools help verify methods, and engineering tools should be checked against real-world standards.
Popular starting points
These calculators cover common entry points: monthly payments, compounding, body metrics, percentages, and data spread. Use the glossary when a term such as principal, compound interest, or standard deviation needs a quick explanation.
Financial
Use these tools for payments, interest, savings, taxes, salary estimates, debt payoff, refinancing, rent-versus-buy comparisons, VAT, and borrowing decisions.
Estimate monthly mortgage payments with principal, interest, taxes, insurance, and loan term inputs.
Financial Loan CalculatorCalculate fixed monthly payments, total payment, and interest for a personal, auto, or general loan.
Financial Auto Loan CalculatorEstimate a car loan payment with vehicle price, down payment, trade-in value, taxes, fees, rate, and term.
Financial Interest CalculatorCalculate simple or compound interest for savings, debt, or investment examples.
Financial Payment CalculatorFind the fixed payment needed to repay a loan over a selected term.
Financial Retirement CalculatorProject retirement savings with contribution growth, inflation-adjusted income targets, and an illustrative withdrawal scenario.
Financial Amortization CalculatorGenerate a compact amortization schedule showing how each payment splits between interest and principal.
Financial Investment CalculatorEstimate investment growth with starting balance, monthly contributions, return, and time horizon.
Financial Inflation CalculatorEstimate how inflation changes future prices and purchasing power over time.
Financial Time Value of Money CalculatorEstimate present value, future value, or future value with recurring monthly contributions under fixed assumptions.
Financial Income Tax Estimate CalculatorEstimate taxable income, tax, after-tax income, and monthly take-home using a simple effective tax rate.
Financial Salary CalculatorConvert salary between hourly, weekly, biweekly, monthly, and annual pay equivalents.
Financial Interest Rate CalculatorApproximate the annual rate needed for a present value to reach a future value over time.
Financial Sales Tax CalculatorCalculate sales tax, discount-adjusted price, and final total from price, tax rate, and optional discount.
Financial Credit Card Payoff CalculatorEstimate how long it may take to pay off a credit card balance and how much interest the payoff plan may cost.
Financial Debt Payoff CalculatorCompare two debts using minimum payments plus an avalanche or snowball extra-payment plan.
Financial Refinance CalculatorCompare an existing loan with a new refinance option using rates, terms, and closing costs.
Financial Rent vs Buy CalculatorCompare renting and buying across a chosen stay length using cash costs, growth assumptions, closing costs, and estimated sale equity.
Financial Paycheck Take-Home Estimate CalculatorModel take-home pay from gross pay and user-entered withholding or deduction assumptions.
Financial VAT CalculatorAdd VAT to a net amount or extract VAT from a gross amount that already includes tax.
Financial Compound Interest CalculatorProject how savings or investments may grow with compounding, contributions, and time.
Fitness & Health
Use these tools for broad body, calorie, pace, and pregnancy timing estimates, not medical decisions.
Calculate body mass index using US or metric units and see the standard BMI category.
Fitness & Health Calorie CalculatorEstimate daily calories using BMR, activity level, and common weight goals.
Fitness & Health Body Fat CalculatorEstimate body fat percentage from sex, age, height, and weight using a BMI-based screening method.
Fitness & Health BMR CalculatorEstimate basal metabolic rate using age, sex, height, and weight.
Fitness & Health Ideal Weight CalculatorCompare common adult ideal weight formulas from sex and height.
Fitness & Health Pace CalculatorCalculate pace, speed, and finish-time relationships for running, walking, or cycling.
Fitness & Health Pregnancy CalculatorEstimate pregnancy week, days pregnant, trimester, and due date from last menstrual period.
Fitness & Health Pregnancy Conception CalculatorEstimate a likely conception date window from due date or last menstrual period.
Fitness & Health Due Date CalculatorEstimate pregnancy due date from last menstrual period, conception date, or IVF transfer date.
Math
Use these tools to check formulas, verify homework, calculate fractions, percentages, geometry, and statistics.
Solve common percentage problems including percent of, percentage change, and what percent one number is of another.
Math Scientific CalculatorUse a fast browser-based calculator for arithmetic, powers, roots, trigonometry, and logarithms.
Math Fraction CalculatorAdd, subtract, multiply, or divide fractions and mixed numbers with simplified results.
Math Random Number GeneratorGenerate random integers or decimal numbers inside a chosen range.
Math Triangle CalculatorCalculate triangle perimeter, area, and angles from three sides or two right-triangle legs.
Math Standard Deviation CalculatorCalculate mean, variance, sample standard deviation, and population standard deviation from a list of numbers.
Date & Time
Use these tools for deadlines, ages, elapsed time, calendar shifts, and duration arithmetic.
Calculate exact age in years, months, and days from a birth date to any selected date.
Date & Time Date Difference CalculatorCount days, weeks, months, and years between two dates.
Date & Time Date CalculatorAdd or subtract days, weeks, months, or years from a start date.
Date & Time Hours CalculatorCalculate elapsed hours between two times, including overnight shifts.
Date & Time Time CalculatorAdd or subtract hours, minutes, and seconds, then convert the result into common time units.
Conversion
Use this section when a measurement needs to be converted before planning, comparing, or estimating.
Convert common length, weight, temperature, and volume units in one simple tool.
Conversion Length ConverterConvert common length units such as feet, meters, miles, kilometers, inches, and centimeters.
Conversion Weight ConverterConvert common weight and mass units including pounds, kilograms, grams, and ounces.
Conversion Temperature ConverterConvert temperatures between Celsius, Fahrenheit, and Kelvin.
Everyday Tools
Use these tools for school grades, tips, discounts, passwords, and practical task-based planning.
Generate strong random passwords with length and character options.
Everyday Tools GPA CalculatorCalculate GPA from course credits and grade points using a weighted average.
Everyday Tools Grade CalculatorCalculate a weighted class grade from assignments, exams, and category weights.
Everyday Tools Tip CalculatorCalculate a restaurant tip, tax estimate, final total, and split amount per person.
Everyday Tools Discount CalculatorCalculate discount amount, discounted price, optional tax, and final total.
Everyday Tools Final Grade CalculatorEstimate the score needed on a final exam or remaining assignment to reach a target class grade.
Engineering & Science
Use these tools for planning estimates that should be verified against standards, site conditions, or network requirements.