Calculator library
Browse calculators by category
Calculastic groups its calculators by the task behind the number: pay and income, business pricing, loan and interest estimates, and measurement conversions. Every calculator keeps formulas visible and supports shareable URLs.
How to choose the right calculator
Start with the input you know.If you know annual salary, start with salary-to-hourly. If you know hourly wage, start with hourly-to-salary.
Check the assumptions.Hours, weeks, tax-rate estimates, loan terms, included costs, and rounding conventions can change the result.
Use related guides for context.Guide pages explain terms such as gross vs net pay, markup vs margin, amortized payments, and unit systems.
Category hubs
Pay & Income Calculators
Convert salary, hourly pay, weekly pay, monthly income, biweekly paychecks, overtime, commission, and freelance rates with schedule-aware calculators.
Guides and comparisons
Read the supporting explanations when the formula depends on definitions, assumptions, or a comparison between similar terms.
Salary and hourly conversions
Compare annual salary with hourly pay across full-time, part-time, after-tax, 40-hour, and US-focused scenarios.
Salary to Hourly Calculator
Convert annual salary into hourly pay using hours per week and paid or worked weeks per year.
Open salary to hourly calculatorSalary to Hourly After Tax Calculator
Estimate net hourly pay from salary using an estimated tax rate and work schedule.
Open salary to hourly after tax calculatorSalary to Hourly USA Calculator
Convert US annual salary into gross hourly pay using weekly hours and paid weeks.
Open salary to hourly usa calculatorSalary to Hourly Part-Time Calculator
Convert part-time salary into hourly pay using custom weekly hours and paid weeks.
Open salary to hourly part-time calculatorHourly to Salary Calculator
Estimate annual gross salary from hourly pay, weekly hours, and paid weeks per year.
Open hourly to salary calculatorHourly to Salary After Tax Calculator
Estimate after-tax annual pay from hourly wages using a tax-rate assumption.
Open hourly to salary after tax calculatorHourly to Salary Part-Time Calculator
Annualize part-time hourly pay using custom weekly hours and paid weeks.
Open hourly to salary part-time calculatorHourly to Salary 40 Hours Calculator
Convert hourly pay to annual salary using a fixed 40-hour weekly schedule.
Open hourly to salary 40 hours calculatorHourly to Salary USA Calculator
Convert US hourly pay into gross annual salary using weekly hours and paid weeks.
Open hourly to salary usa calculatorPay period conversions
Annualize monthly, weekly, and biweekly pay, or convert pay periods into hourly equivalents when schedule matters.
Monthly to Hourly Calculator
Convert monthly income into an hourly wage using annualized income and work schedule.
Open monthly to hourly calculatorWeekly to Hourly Calculator
Convert weekly income into an hourly wage using weekly hours.
Open weekly to hourly calculatorMonthly to Salary Calculator
Convert monthly income into annual salary or yearly pay using a 12-month year.
Open monthly to salary calculatorWeekly to Salary Calculator
Convert weekly pay into annual salary or yearly income using paid weeks per year.
Open weekly to salary calculatorBiweekly to Yearly Pay Calculator
Convert a biweekly paycheck into annual pay using 26 pay periods per year.
Open biweekly to yearly pay calculatorBiweekly to Hourly Calculator
Convert biweekly pay into an hourly equivalent using 26 pay periods and weekly hours.
Open biweekly to hourly calculatorMonthly to Yearly Income Calculator
Convert stable monthly income into a yearly gross income estimate.
Open monthly to yearly income calculatorVariable and independent work
Estimate overtime, commission, and freelance rates when pay is not a simple fixed salary.
Overtime Pay Calculator
Calculate gross overtime pay using base hourly rate, overtime hours, and multiplier.
Open overtime pay calculatorFreelance Hourly Rate Calculator
Plan a freelance hourly rate from income target, billable hours, overhead, and tax reserves.
Open freelance hourly rate calculatorCommission Calculator
Estimate flat-rate gross commission from sales amount and commission percentage.
Open commission calculatorBusiness & Pricing Calculators
Calculate margin, markup, gross profit, break-even volume, unit pricing, and cost-plus pricing for practical business decisions.
Guides and comparisons
Read the supporting explanations when the formula depends on definitions, assumptions, or a comparison between similar terms.
Profit and pricing
Measure profit dollars, margin percentage, markup, and cost-plus selling prices.
Profit Margin Calculator
Calculate profit margin percentage and profit dollars from revenue and cost.
Open profit margin calculatorGross Profit Calculator
Calculate gross profit dollars and gross margin percentage from revenue and cost.
Open gross profit calculatorMarkup Calculator
Calculate markup amount, markup percentage, and the related margin percentage.
Open markup calculatorCost Plus Pricing Calculator
Calculate selling price, profit per unit, and margin from cost plus target markup.
Open cost plus pricing calculatorUnit economics
Normalize prices and estimate the sales volume needed to cover fixed costs.
Sales cost context
Estimate flat commission when sales payouts affect pricing or profitability.
Loan & Interest Calculators
Estimate fixed loan payments, total interest, personal loan payments, auto loan payments, and simple interest.
Guides and comparisons
Read the supporting explanations when the formula depends on definitions, assumptions, or a comparison between similar terms.
Amortized loan payments
Estimate monthly principal-and-interest payments and lifetime interest for fixed-rate loans.
Loan Payment Calculator
Estimate amortized monthly payment, total paid, and total interest.
Open loan payment calculatorTotal Loan Interest Calculator
Estimate total interest, total paid, and monthly payment for an amortized loan.
Open total loan interest calculatorPersonal Loan Payment Calculator
Estimate monthly payment, total paid, and total interest for a personal loan.
Open personal loan payment calculatorAuto Loan Payment Calculator
Estimate a vehicle loan payment from price, down payment, rate, and term.
Open auto loan payment calculatorSimple interest
Use simple interest when interest is charged on principal without compounding or amortization.
Conversion Calculators
Convert length, weight, temperature, volume, area, time, data, speed, and kitchen units with fast calculators, visible formulas, examples, and rounding notes.
Guides and comparisons
Read the supporting explanations when the formula depends on definitions, assumptions, or a comparison between similar terms.
Length conversions
Convert everyday length measurements between imperial and metric units.
Inches to CM Calculator
Convert inches to centimeters with the exact 2.54 cm per inch factor.
Open inches to cm calculatorCM to Inches Calculator
Convert centimeters to inches by dividing centimeters by 2.54.
Open cm to inches calculatorFeet to Meters Calculator
Convert feet to meters using the exact 0.3048 meter per foot factor.
Open feet to meters calculatorMeters to Feet Calculator
Convert meters to feet by dividing meters by 0.3048.
Open meters to feet calculatorWeight conversions
Convert pounds and kilograms for body weight, shipping, luggage, and product weights.
Temperature conversions
Convert Fahrenheit and Celsius for weather, cooking, appliances, and science references.
Volume conversions
Convert U.S. liquid gallons and liters for fuel, containers, liquids, and product volumes.
Area conversions
Convert square feet and square meters for rooms, real estate, floor plans, and projects.
Square Feet to Square Meters Calculator
Convert square feet to square meters using 0.09290304 square meters per square foot.
Open square feet to square meters calculatorSquare Meters to Square Feet Calculator
Convert square meters to square feet using 10.7639104167 square feet per square meter.
Open square meters to square feet calculatorTime conversions
Convert minutes, hours, days, and weeks for work logs, schedules, deadlines, and planning.
Minutes to Hours Calculator
Convert minutes to hours by dividing minutes by 60.
Open minutes to hours calculatorHours to Minutes Calculator
Convert hours to minutes by multiplying hours by 60.
Open hours to minutes calculatorDays to Weeks Calculator
Convert days to weeks by dividing days by 7.
Open days to weeks calculatorWeeks to Days Calculator
Convert weeks to days by multiplying weeks by 7.
Open weeks to days calculatorData storage conversions
Convert KB, MB, GB, and TB for file sizes, downloads, storage plans, and device capacity.
KB to MB Calculator
Convert kilobytes to megabytes using 1 MB = 1,024 KB.
Open kb to mb calculatorMB to GB Calculator
Convert megabytes to gigabytes using 1 GB = 1,024 MB.
Open mb to gb calculatorGB to MB Calculator
Convert gigabytes to megabytes using 1 GB = 1,024 MB.
Open gb to mb calculatorTB to GB Calculator
Convert terabytes to gigabytes using 1 TB = 1,024 GB.
Open tb to gb calculatorSpeed conversions
Convert miles per hour and kilometers per hour for driving, travel, cycling, and road speeds.
Cooking and measurement conversions
Convert U.S. cups and milliliters for recipes, baking, meal prep, and kitchen measurement.