All Calculators
Browse our complete library of free online calculators — financial, fitness, math, and everyday tools, all in one place. No sign-up, no email, no fine print. Just pick a tool, enter your numbers, and get an instant answer
137 free calculators
Financial Calculators
50/30/20 Budget Calculator
Organize your net take-home salary into Needs (50%), Wants (30%), and Wealth Savings (20%).
Use calculator →Amortization Calculator
Full monthly and annual loan amortization schedules with downloadable CSV reports.
Use calculator →Annuity & Annuity Payout Calculator
Calculate future annuity balances or fixed guaranteed monthly retirement payouts.
Use calculator →APR vs. APY Interest Rate Converter
Convert nominal APR to effective Annual Percentage Yield (APY) based on compounding.
Use calculator →Auto Lease Calculator
Calculate monthly vehicle lease payments based on MSRP, negotiated selling price, and money factor.
Use calculator →Auto Loan Calculator
Calculate monthly car payments factoring in vehicle price, trade-in equity, sales tax, and dealer fees.
Use calculator →Boat & RV Loan Calculator
Calculate marine and RV installment loan payments up to 15-20 year terms.
Use calculator →Canadian Mortgage Calculator
Calculate Canadian mortgage payments with semi-annual compounding and CMHC insurance rules.
Use calculator →CD (Certificate of Deposit) Calculator
Calculate guaranteed earnings and APY interest on bank certificates of deposit.
Use calculator →College Cost & 529 Savings Calculator
Project future university tuition inflation and required monthly 529 plan savings.
Use calculator →Commission Calculator
Calculate sales rep and real estate agent commission earnings based on tiered rates.
Use calculator →Compound Interest Calculator
Project future investment growth with recurring deposits, compounding frequencies, and inflation adjustments.
Use calculator →Credit Card Payoff Calculator
Calculate how long to pay off credit card balances and discover massive interest savings over minimums.
Use calculator →Debt Consolidation Calculator
Compare multiple high-interest debts against a single low-interest consolidation loan.
Use calculator →Debt-to-Income (DTI) Calculator
Calculate your Front-End and Back-End Debt-to-Income ratios for mortgage and loan eligibility.
Use calculator →Depreciation Calculator (Straight-Line & MACRS)
Calculate annual asset depreciation expense and book value schedules.
Use calculator →Discount & Percent Off Calculator
Calculate sale prices, dollar savings, and stacked double discounts.
Use calculator →Down Payment Calculator
Calculate target down payment amounts, PMI elimination milestones, and savings timelines.
Use calculator →Estate Tax Calculator
Calculate federal estate tax liability and exemption thresholds for high-net-worth wealth transfers.
Use calculator →FHA Loan Calculator
Calculate FHA mortgage payments with 3.5% down and upfront/annual Mortgage Insurance Premiums (MIP).
Use calculator →HELOC Calculator
Calculate Home Equity Line of Credit draw period payments and repayment schedules.
Use calculator →House Affordability Calculator
Discover how much house you can afford based on your income, monthly debts, and down payment.
Use calculator →Income Tax Calculator
Estimate your Federal, State, and FICA payroll taxes with marginal bracket breakdowns.
Use calculator →Inflation Calculator
Calculate the loss of purchasing power on uninvested cash and future equivalent costs.
Use calculator →Loan Calculator
Calculate monthly payments, interest cost, and amortization for any installment loan.
Use calculator →Margin & Markup Calculator
Calculate Gross Profit Margin, Markup percentage, and price points from COGS.
Use calculator →Marriage Tax Calculator (Bonus / Penalty)
Discover if getting married results in a tax bonus or penalty for dual vs single earners.
Use calculator →Mortgage Calculator
Calculate monthly mortgage payment including principal, interest, taxes, insurance (PITI), and HOA.
Use calculator →Mortgage Payoff Calculator
See how extra monthly, annual, or lump-sum payments shave years off your mortgage and save thousands.
Use calculator →Mutual Fund & ETF Fee Drag Calculator
Calculate how high management expense ratios (1.0%+) eat into your lifetime portfolio returns.
Use calculator →Present Value & Future Value (TVM) Calculator
Calculate the Time Value of Money (PV, FV, Discount Rate, and Compounding).
Use calculator →Refinance Calculator
Calculate monthly savings and exact break-even timeline for refinancing your existing mortgage.
Use calculator →Rent vs. Buy Calculator
Determine whether renting or buying builds greater long-term net wealth over your time horizon.
Use calculator →Rental Property Calculator
Analyze real estate investment cash flow, Cap Rate, Net Operating Income (NOI), and Cash-on-Cash return.
Use calculator →Retirement & 401(k) Calculator
Plan your retirement nest egg, employer match compounding, and safe 4% rule withdrawal income.
Use calculator →RMD (Required Minimum Distribution) Calculator
Calculate mandatory IRS Required Minimum Distributions starting at age 73.
Use calculator →ROI (Return on Investment) Calculator
Calculate total ROI, annualized CAGR, and capital payback periods on investments.
Use calculator →Roth IRA vs. Traditional IRA Calculator
Compare after-tax retirement wealth between a tax-free Roth IRA and a pre-tax Traditional IRA.
Use calculator →Salary & Take-Home Paycheck Calculator
Calculate exact weekly, bi-weekly, semi-monthly, and monthly net paycheck amounts.
Use calculator →Sales Tax & VAT Calculator
Add sales tax to pre-tax prices or extract embedded VAT / GST from gross receipts.
Use calculator →Savings Goal Calculator
Calculate how much to save monthly to reach any financial goal by your target date.
Use calculator →Simple Interest Calculator
Calculate linear simple interest (I = P * r * t) and compare with compound growth.
Use calculator →Social Security Calculator
Estimate your monthly Social Security retirement checks at ages 62, 67 (FRA), and 70.
Use calculator →Student Loan Calculator
Calculate student loan repayments under standard, extended, and accelerated payoff plans.
Use calculator →UK Mortgage Calculator
Calculate UK mortgage payments, LTV ratios, and Stamp Duty Land Tax (SDLT).
Use calculator →VA Mortgage Calculator
Calculate VA loan payments with 0% down payment and no monthly mortgage insurance (PMI).
Use calculator →Fitness & Health Calculators
Anorexic BMI Calculator
Look up standard BMI classification bands, including the clinically underweight range, for reference.
Use calculator →Army Body Fat Calculator
Estimate body fat percentage using the U.S. Army circumference-based method.
Use calculator →BAC Calculator
Estimate blood alcohol concentration using the Widmark formula. For education only.
Use calculator →BMI Calculator
Calculate your Body Mass Index and see your weight category.
Use calculator →BMR Calculator
Calculate your Basal Metabolic Rate (calories burned at rest).
Use calculator →Body Fat Calculator
Estimate body fat percentage using the U.S. Navy circumference method.
Use calculator →Body Surface Area Calculator
Estimate body surface area (BSA) using the Du Bois formula.
Use calculator →Body Type Calculator
Estimate your body type (somatotype) from your measurements.
Use calculator →Calorie Calculator
Estimate your daily calorie needs to maintain, lose or gain weight.
Use calculator →Calories Burned Calculator
Estimate calories burned during an activity using MET values.
Use calculator →Carbohydrate Calculator
Estimate your recommended daily carbohydrate intake.
Use calculator →Conception Calculator
Estimate your most likely conception window.
Use calculator →Due Date Calculator
Estimate your baby's due date from your last menstrual period or conception date.
Use calculator →Fat Intake Calculator
Estimate your recommended daily fat intake based on total calories.
Use calculator →GFR Calculator
Estimate glomerular filtration rate (kidney function) using the CKD-EPI formula.
Use calculator →Healthy Weight Calculator
Find the healthy weight range for your height, based on standard BMI cut-offs.
Use calculator →Ideal Weight Calculator
Estimate your ideal body weight using several established formulas.
Use calculator →Lean Body Mass Calculator
Estimate your lean body mass (fat-free mass) using the Boer formula.
Use calculator →Macro Calculator
Get personalized protein, carb and fat targets based on your calories.
Use calculator →One Rep Max Calculator
Estimate your one-rep max (1RM) using the Epley formula.
Use calculator →Overweight Calculator
Check whether your weight falls into the overweight BMI range and see how much is above the healthy range.
Use calculator →Ovulation Calculator
Predict your next fertile window and ovulation day.
Use calculator →Pace Calculator
Calculate running pace, time or distance - given the other two.
Use calculator →Period Calculator
Predict your next few period start dates based on your cycle history.
Use calculator →Pregnancy Calculator
Estimate your due date and current week of pregnancy from your last period.
Use calculator →Pregnancy Conception Calculator
Estimate your likely conception date from your due date or last period.
Use calculator →Pregnancy Weight Gain Calculator
See the recommended healthy weight gain range for your pregnancy based on pre-pregnancy BMI.
Use calculator →Protein Calculator
Estimate your recommended daily protein intake based on weight and activity.
Use calculator →Target Heart Rate Calculator
Find your target heart rate training zones using the Karvonen method.
Use calculator →TDEE Calculator
Estimate your Total Daily Energy Expenditure.
Use calculator →Weight Watcher Points Calculator
Estimate a SmartPoints-style value for a food based on its nutrition facts.
Use calculator →Math Calculators
Area Calculator
Calculate the area of a square, rectangle, triangle, circle, trapezoid or parallelogram.
Use calculator →Average Calculator
Find the average (mean) of a list of numbers.
Use calculator →Basic Calculator
A simple two-number calculator for addition, subtraction, multiplication, division and exponents.
Use calculator →Big Number Calculator
Add, subtract, multiply or divide very large whole numbers with full precision.
Use calculator →Binary Calculator
Convert between decimal and binary numbers.
Use calculator →Circle Calculator
Enter any one property of a circle (radius, diameter, circumference or area) to find the rest.
Use calculator →Common Factor Calculator
List all factors shared by two numbers.
Use calculator →Confidence Interval Calculator
Calculate a confidence interval for a sample mean.
Use calculator →Distance Calculator
Find the straight-line distance between two points on a plane.
Use calculator →Exponent Calculator
Raise a base to any power, including negative or fractional exponents.
Use calculator →Factor Calculator
List every factor of a whole number.
Use calculator →Fraction Calculator
Add, subtract, multiply or divide two fractions and simplify the result.
Use calculator →Greatest Common Factor Calculator
Find the greatest common factor (GCF / GCD) of two or more numbers.
Use calculator →Half-Life Calculator
Calculate the remaining amount of a substance after a given time, based on its half-life.
Use calculator →Hex Calculator
Convert between decimal and hexadecimal numbers.
Use calculator →Least Common Multiple Calculator
Find the least common multiple (LCM) of two or more numbers.
Use calculator →Log Calculator
Calculate the logarithm of a number in base 10, base 2, natural log, or a custom base.
Use calculator →Long Division Calculator
Divide two numbers and see the quotient, remainder and decimal result.
Use calculator →Matrix Calculator
Add, subtract, multiply or find the determinant of 2x2 matrices.
Use calculator →Mean, Median, Mode, Range Calculator
Quickly find the mean, median, mode and range of a data set.
Use calculator →Number Sequence Calculator
Generate an arithmetic, geometric or Fibonacci-style sequence and find the sum.
Use calculator →P-value Calculator
Calculate the p-value for a given z-score and test type.
Use calculator →Percent Error Calculator
Calculate the percent error between an experimental and theoretical value.
Use calculator →Percentage Calculator
Find a percentage of a number, what percent one number is of another, or percent change.
Use calculator →Permutation and Combination Calculator
Calculate the number of permutations (nPr) or combinations (nCr).
Use calculator →Prime Factorization Calculator
Break a number down into its prime factors.
Use calculator →Probability Calculator
Calculate the combined probability of two events (AND / OR).
Use calculator →Pythagorean Theorem Calculator
Find a missing side of a right triangle using a^2 + b^2 = c^2.
Use calculator →Quadratic Formula Calculator
Solve ax^2 + bx + c = 0 for real or complex roots.
Use calculator →Random Number Generator
Generate one or more random numbers within a range.
Use calculator →Ratio Calculator
Simplify a ratio, or scale it to find an equivalent value.
Use calculator →Right Triangle Calculator
Solve a right triangle's missing side, angles and area from two known sides.
Use calculator →Root Calculator
Calculate the nth root of a number (square root, cube root, or any root).
Use calculator →Rounding Calculator
Round a number to a chosen number of decimal places, or round up/down.
Use calculator →Sample Size Calculator
Estimate the sample size needed for a survey given confidence level and margin of error.
Use calculator →Scientific Calculator
Evaluate expressions with +, -, *, /, ^, parentheses and functions like sqrt, sin, cos, tan, log, ln.
Use calculator →Scientific Notation Calculator
Convert a number to and from scientific notation.
Use calculator →Slope Calculator
Find the slope, y-intercept and equation of the line through two points.
Use calculator →Standard Deviation Calculator
Calculate mean, variance and standard deviation for a set of numbers.
Use calculator →Statistics Calculator
Get a full statistical summary (mean, median, mode, range, variance, std dev) for a data set.
Use calculator →Surface Area Calculator
Calculate the total surface area of a cube, box, sphere, cylinder or cone.
Use calculator →Triangle Calculator
Enter three side lengths to get the area, perimeter, angles and triangle type.
Use calculator →Volume Calculator
Calculate the volume of a cube, box, sphere, cylinder, cone or square pyramid.
Use calculator →Z-score Calculator
Find the z-score for a value given the mean and standard deviation of a distribution.
Use calculator →Complete Guide to All Calculators
Your tour of all 137 free calculators on CalcDune.
How to use our calculators
Every tool on CalcDune follows the same simple flow, no matter the category:
- Pick a calculator. Browse the categories above or use search to jump straight to the tool you need.
- Enter your numbers. Each calculator asks only for the inputs it needs — nothing extra.
- Get instant results. Answers appear as you type, with a clear breakdown and the formula shown.
- Adjust and compare. Change your inputs to explore different scenarios side by side.
No account, no downloads, no data stored. Everything runs locally in your browser.
Calculator FAQs
Are all 137 calculators really free?
Yes — every calculator on CalcDune is 100% free, with unlimited use and no sign-up required.
Which calculator should I start with?
Try a popular one: the mortgage calculator for home loans, the BMI calculator for health, or browse a category above to see everything in one place.
Do the calculators work on mobile?
Absolutely. Every tool is fully responsive and works on phones, tablets, and desktops.
Is my data private?
Yes. All calculations happen in your browser — your numbers are never sent to our servers or stored anywhere.
Popular calculators
Start with the tools visitors use most.