Embed Calculators
Embed powerful calculators on your website. Browse our library of 5,034+ calculators and add them to any site with a simple embed code.
Investing Retirement
Investment Return Calculator
Calculate the total and annualized return on your investment. Compare performance across different time periods.
Rule of 72 Calculator
Quickly estimate how long it takes to double your money. The Rule of 72 gives a simple approximation based on your interest rate.
Annuity Calculator
Calculate the future value and present value of an annuity. Plan your retirement income or investment returns.
Retirement Age Calculator
Calculate when you can retire based on savings, contributions, and retirement goals. See retirement age and years needed.
IRR Calculator
Calculate Internal Rate of Return (IRR) for an investment with multiple cash flows. Essential for comparing investment opportunities and project analysis.
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Math Statistics
Percentage Calculator
Calculate percentages easily — find a percentage of a number, percentage increase/decrease, and percentage change between two values.
Fraction Calculator
Add, subtract, multiply, or divide fractions. Get simplified results, mixed numbers, and decimal equivalents.
Standard Deviation Calculator
Calculate the mean, median, standard deviation, and variance for a set of numbers. Supports both population and sample calculations.
Probability Calculator
Calculate probability of single events, combined events (AND/OR), permutations, and combinations.
GPA Calculator
Calculate your semester GPA and cumulative GPA. Enter course grades and credit hours for an instant result.
Average Calculator
Calculate mean, median, mode, range, geometric mean, and harmonic mean of a set of numbers.
Quadratic Equation Solver
Solve quadratic equations (ax² + bx + c = 0). Find roots, discriminant, vertex, and axis of symmetry with a visual graph.
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Health Fitness
BMI Calculator
Calculate your Body Mass Index (BMI) to assess your weight category. Supports both imperial and metric units.
Blood Alcohol Content (BAC) Calculator
Estimate your blood alcohol content using the Widmark formula. See your current BAC, peak BAC, impairment level, and time to sobriety based on drink type, body weight, and gender.
Calorie & TDEE Calculator
Calculate your Total Daily Energy Expenditure (TDEE) and daily calorie needs based on your age, weight, height, and activity level.
Body Fat Percentage Calculator
Estimate your body fat percentage using the US Navy method. Determine your body composition category and fat vs lean mass.
Ideal Weight Calculator
Calculate your ideal body weight using four scientific formulas. See your healthy weight range based on BMI and height.
Water Intake Calculator
Calculate how much water you should drink daily based on your weight, activity level, and climate.
One Rep Max (1RM) Calculator
Estimate your one-rep max for any lift based on weight and reps. Get a training percentage chart for programming your workouts.
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Physics Expanded
Fluid Dynamics (Bernoulli) Calculator
Apply Bernoulli's equation to calculate pressure or velocity changes in an ideal fluid between two points at different heights.
Buoyancy Calculator
Calculate the buoyant force, net force, and whether an object floats or sinks using Archimedes' principle: F_b = ρ_fluid × V × g.
Capacitance Calculator
Calculate the capacitance of a parallel plate capacitor from plate area, separation, and dielectric constant using C = ε₀εᵣA/d.
Diffraction Grating Calculator
Calculate diffraction angles for each order using d sin(θ) = mλ. Find the maximum observable order and angular dispersion.
Doppler Effect Calculator
Calculate the observed frequency when a sound source and observer are in relative motion using the Doppler effect equation.
Electromagnetic Wave Calculator
Calculate the wavelength, photon energy, and momentum of an electromagnetic wave from its frequency using c = fλ and E = hf.
Inductance Calculator
Calculate the inductance of a solenoid from turns, length, cross-section area, and core permeability using L = μ₀μᵣN²A/l.
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Loans Debt
Auto Loan Calculator
Calculate your monthly car payment, total interest, and view a full repayment schedule. Includes sales tax and trade-in value.
Credit Card Payoff Calculator
See how long it takes to pay off your credit card and how much interest you'll pay. Compare different payment strategies.
Personal Loan Calculator
Calculate monthly payments and total interest for a personal loan. Compare different rates and terms to find the best deal.
Debt-to-Income Ratio Calculator
Calculate your debt-to-income (DTI) ratio to understand your borrowing capacity. Lenders use DTI to determine mortgage and loan eligibility.
Student Loan Repayment Calculator
Calculate your student loan monthly payment, total interest, and payoff timeline. See how extra payments accelerate payoff.
Loan-to-Value Ratio Calculator
Calculate your loan-to-value (LTV) ratio for mortgages and loans. Understand your equity and risk level.
Loan Comparison Calculator
Compare two loans side-by-side. See monthly payments, total cost, and interest differences to choose the best option.
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Clinical Medicine
IV Drip Rate Calculator
Calculate drops per minute and mL per hour for IV fluid administration based on volume, time, and drop factor.
Drug Dosage by Weight Calculator
Calculate medication dosage based on patient weight (mg/kg), dosing frequency, and drug concentration.
Pediatric Dosing Calculator
Calculate age- and weight-adjusted medication doses for children using Young's, Clark's, and Fried's rules.
Creatinine Clearance Calculator
Calculate creatinine clearance using the Cockcroft-Gault equation for renal function assessment and drug dose adjustment.
APACHE II Score Calculator
Calculate the APACHE II (Acute Physiology and Chronic Health Evaluation) score for ICU mortality prediction.
Glasgow Coma Scale Calculator
Calculate the Glasgow Coma Scale (GCS) score from eye, verbal, and motor responses for assessing consciousness level.
MELD Score Calculator
Calculate the Model for End-Stage Liver Disease (MELD) score to assess severity of chronic liver disease and transplant priority.
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Actuarial
Life Expectancy Calculator
Calculate life expectancy based on age, gender, lifestyle factors, and health metrics. Uses actuarial science principles.
Mortality Rate Calculator
Calculate mortality rates, death probabilities, and survival probabilities using actuarial methods.
Insurance Premium Calculator
Calculate life insurance premiums using actuarial principles. Factors in age, gender, health status, and risk factors.
Annuity Present Value Calculator
Calculate present value and future value of annuities. Supports ordinary and annuity due payments with various frequencies.
Risk Assessment Calculator
Calculate Value at Risk (VaR), Conditional VaR, and risk metrics for actuarial risk assessment.
Pension Benefit Calculator
Calculate pension benefits, present value, and retirement income using actuarial methods.
Actuarial Reserve Calculator
Calculate required actuarial reserves for insurance policies and pension plans using actuarial methods.
+ 14 more in this category
Geometry
Area Calculator
Calculate the area and perimeter of common shapes — rectangle, circle, triangle, trapezoid, and ellipse.
Volume Calculator
Calculate the volume and surface area of common 3D shapes — cube, box, sphere, cylinder, and cone. Convert between units.
Pythagorean Theorem Calculator
Find the missing side of a right triangle using the Pythagorean theorem. Calculate area, perimeter, and angles.
Slope Calculator
Calculate the slope, distance, midpoint, and line equation from two points. Visualize rise over run.
Circle Calculator
Calculate radius, diameter, circumference, area, sector area, and arc length of a circle from any known value.
Triangle Calculator
Calculate area, angles, heights, perimeter, inradius, and circumradius of any triangle from three sides.
Surface Area Calculator
Calculate surface area, lateral area, and volume for cubes, spheres, cylinders, cones, and pyramids.
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Income Optimization
Side Hustle Break-Even Calculator
Calculate how many hours and months your side hustle needs to break even. Compare your effective hourly rate against your opportunity cost to see if it's truly worth your time.
Overtime vs Second Job Calculator
Compare the net income from working overtime at your current job versus taking on a second job. Factor in tax rates, commute costs, and time to find the better option.
Raise Negotiation Calculator
See the true lifetime impact of a salary raise. Calculate how a percentage increase compounds over your career, including effects on 401(k) matching and total compensation.
Freelance Rate Calculator
Compute the hourly rate you need to charge as a freelancer to hit your desired income. Accounts for self-employment taxes, health insurance, business expenses, and profit margin.
Gig Economy Earnings Calculator
Calculate your true net earnings from gig work like rideshare or delivery. Factor in platform fees, vehicle costs, gas, and self-employment taxes to see your real hourly rate.
Commission Structure Comparator
Compare a flat commission plan against a tiered commission structure. See which pays more at different sales levels and find the break-even point.
Passive Income Goal Calculator
Calculate how much you need invested to generate your target monthly passive income. See your progress toward financial independence and how long it will take to reach your goal.
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Civil Engineering
Beam Load Calculator
Calculate maximum shear, bending moment, and deflection for simply supported and cantilever beams under uniform or point loads.
Concrete Mix Design Calculator
Design a concrete mix by specifying target strength, water-cement ratio, and cement content. Get weights for cement, water, fine and coarse aggregates per cubic yard.
Rebar Spacing Calculator
Calculate rebar spacing, bars per foot, and steel ratio for concrete slabs. Checks ACI code compliance for maximum spacing.
Soil Bearing Capacity Calculator
Calculate ultimate and allowable soil bearing capacity using Terzaghi's equation. Inputs include soil cohesion, friction angle, and foundation geometry.
Retaining Wall Design Calculator
Calculate active earth pressure, overturning moment, and sliding forces on a retaining wall using Rankine's theory.
Storm Drain Sizing Calculator
Size storm drain pipes using the Rational Method for flow estimation and Manning's equation for pipe capacity. Selects nearest standard pipe size.
Traffic Signal Timing Calculator
Calculate signal green time, effective green, volume-to-capacity ratio, and average delay per vehicle for signalized intersections.
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Technology
Password Strength Calculator
Check how strong your password could be based on length and character types. See estimated time to crack.
Binary/Hex/Decimal Converter
Convert between binary, octal, decimal, and hexadecimal number systems. Includes bit count, byte size, and ASCII character lookup.
Hex Converter
Convert between hexadecimal, decimal, binary, and octal number systems. Essential for programming and computer science.
Decimal Converter
Convert decimal numbers to binary, hexadecimal, and octal. Essential tool for programming and computer science.
Download Time Calculator
Calculate how long it takes to download a file at various internet speeds. Compare download times across different connection speeds.
Color Converter
Convert colors between HEX, RGB, HSL, and CMYK formats. Enter RGB values and get all other representations instantly.
Subnet Calculator
Calculate subnet mask, network address, broadcast address, usable host range, and CIDR notation for any IP address.
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Aviation
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Zero Budget Planning
Zero-Based Budget Builder
Allocate every dollar of your income to a category until your remaining balance hits zero. The gold standard of intentional budgeting.
Envelope Allocation Calculator
Distribute your income across virtual envelopes by priority. A digital take on the classic cash envelope budgeting system.
Variable Income Budget Calculator
Build a zero-based budget for freelancers and gig workers with fluctuating income. Plan for low, average, and high earning months.
Biweekly Budget Adjuster Calculator
Recalculate your budget for months with 3 pay periods. Biweekly pay gives you 2 extra paychecks per year — plan how to use them.
Budget Surplus Allocator Calculator
Optimize where to direct leftover dollars using a priority-based waterfall: emergency fund, retirement match, high-interest debt, then savings goals.
Irregular Expense Smoother Calculator
Spread annual, quarterly, and bi-annual bills into a predictable monthly amount so irregular expenses never surprise your budget.
Sinking Fund Calculator
Plan monthly contributions for a future expense. Set a target, a deadline, and see exactly how much to save each month.
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Mechanical Engineering
Shaft Design Calculator
Design a shaft for combined bending and torsional loads using the von Mises failure criterion. Calculates minimum diameter and stresses.
Gear Ratio Calculator
Calculate gear ratio, output speed, output torque, and mechanical advantage for a simple gear pair.
Belt Drive Design Calculator
Design V-belt or flat belt drives. Calculate belt length, speed ratio, belt speed, and tight/slack side tensions for power transmission.
Spring Design Calculator
Design helical compression springs. Calculate spring rate, deflection, shear stress with Wahl correction, and free/solid lengths.
Bearing Life Calculator
Calculate L10 bearing life in revolutions and hours using the ISO 281 basic rating life equation for ball and roller bearings.
Thermal Expansion Calculator
Calculate linear thermal expansion, thermal strain, and restrained thermal stress for engineering materials subjected to temperature changes.
Heat Exchanger Sizing Calculator
Size a counterflow heat exchanger using the LMTD method. Calculate heat duty, log mean temperature difference, and required surface area.
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Air Quality
AQI Calculator
Air Quality Index from pollutant concentrations (PM2.5, PM10, O3, CO, SO2, NO2) using EPA breakpoint tables.
+ 11 more in this category
Budgeting Savings
Tip Splitter Calculator
Split the bill and tip evenly among multiple people. Calculate how much each person should pay including tip.
Savings Goal Calculator
Find out how much you need to save each month to reach your savings goal. See how interest helps you get there faster.
Net Worth Calculator
Calculate your net worth by listing your assets and liabilities. Track your financial progress over time.
Emergency Fund Calculator
Calculate how much you need in your emergency fund and how long it will take to build one. Experts recommend 3-6 months of expenses.
Inflation Calculator
See how inflation erodes purchasing power over time. Calculate the future cost of goods and what your money will really be worth.
Cost of Living Comparison
Compare cost of living between any US cities, states, or ZIP codes. See salary equivalents, category-by-category breakdowns, tax differences, and what you'd need to earn to maintain your lifestyle.
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Hr Payroll
Salary Calculator
Convert your salary between annual, monthly, biweekly, weekly, daily, and hourly rates. Includes estimated federal tax and take-home pay.
Hourly to Salary Calculator
Convert your hourly wage to an annual salary, monthly, biweekly, and daily pay. See estimated after-tax income.
Overtime Pay Calculator
Calculate your overtime pay based on hourly rate, hours worked, and overtime multiplier. Includes double-time calculations.
Billable Hours Calculator
Track billable vs non-billable hours and calculate weekly, monthly, and annual revenue. Optimize your billing rate.
Severance Pay Calculator
Estimate severance pay based on years of service and salary. Calculate your severance package.
Payroll Tax Calculator
Calculate payroll taxes including federal, state, Social Security, and Medicare. Estimate take-home pay.
Compensation & Income Calculator
Complete compensation calculator — convert hourly to salary, calculate overtime pay, determine freelance rates, estimate payroll taxes, and project Social Security benefits.
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Statistics
Z-Score Calculator
Calculate the z-score (standard score) for any value in a normal distribution. Find the percentile ranking and probability associated with your data point.
Confidence Interval Calculator
Calculate the confidence interval for a population mean. Determine the margin of error and range where the true population parameter likely falls.
Sample Size Calculator
Determine the required sample size for your survey or study. Calculate how many responses you need for statistically significant results.
ANOVA Calculator
Perform a one-way ANOVA (Analysis of Variance) to compare means across three groups and determine if differences are statistically significant.
Bayesian Prior Calculator
Apply Bayes' theorem to update a prior probability given test sensitivity and false positive rate. Calculate the posterior probability after a positive or negative result.
Chi-Square Test Calculator
Perform a chi-square goodness-of-fit test comparing observed and expected frequencies across four categories.
Confidence Interval Calculator
Calculate the confidence interval for a population mean using sample data. Uses z-based approximation suitable for large samples.
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Small Business
Discount Calculator
Calculate discounted prices, savings amount, and discount percentage. Perfect for sales and pricing.
Sales Commission Calculator
Calculate sales commission earnings including base salary, commission rate, and quota bonuses. See total earnings and quota achievement.
Break-Even Analysis Calculator
Calculate break-even point, profit analysis, and margin of safety. Essential for business planning and pricing decisions.
Freelance Rate Calculator
Calculate your ideal freelance hourly rate based on desired salary, expenses, taxes, and billable hours. Ensure you're pricing your services correctly.
Business Valuation Calculator
Estimate business value using SDE multiple, revenue multiple, and DCF methods.
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Construction Diy
Square Footage Calculator
Calculate the square footage of a rectangular area. Convert between square feet, yards, and meters. Estimate total cost based on price per square foot.
Paint Calculator
Calculate how many gallons of paint you need for a room. Accounts for doors, windows, and multiple coats.
Paint Coverage Calculator
Calculate how much paint you need for your room. Estimate gallons and quarts based on room dimensions and coverage.
Tile Calculator
Calculate how many tiles you need for your floor or wall project. Account for waste and see total tiles needed.
Flooring Calculator
Calculate how much flooring you need for a room. Accounts for waste, calculates boxes needed, and estimates cost.
Lumber Calculator
Calculate board feet for lumber purchases. Enter dimensions and quantity to get total board footage and estimated cost.
Drywall Calculator
Calculate how many drywall sheets, joint tape, compound, and screws you need for your project.
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