100% Free Online Calculators
Fast, free calculators for money, health, math and everyday life. No sign-up — pick a tool and get your answer in seconds.
Most Popular Calculators
The tools visitors use the most — quick answers to everyday questions.
📍 Midpoint Calculator NEW
The point exactly halfway between two points, with distance and slope.
✏️ Equation of a Line Calculator NEW
Build a line equation from two points, a point and slope, or slope and intercept.
🏹 Parabola Calculator NEW
Vertex, focus, directrix and roots of a parabola, with a drawn graph.
📐 Derivative Calculator NEW
Differentiate any function symbolically — exact f′(x).
∫ Integral Calculator NEW
Antiderivatives plus definite integrals with your bounds.
🧮 Equation Solver NEW
Solve equations exactly or numerically, roots included.
📈 Graphing Calculator NEW
Plot functions, zoom, trace values and build a table of values.
📊 T-Test Calculator NEW
One-sample, two-sample and paired t-tests with p-values.
→ Limit Calculator NEW
Limits of functions with left and right hand checks.
🛡️ Life Insurance Calculator NEW
How much cover you need from income, debts and future costs.
📊 Balance Sheet Calculator NEW
Assets, liabilities and net worth in one clean snapshot.
🧾 1099 Tax Calculator NEW
SE tax, income tax and quarterly estimates for freelancers.
⏱️ Time to Decimal Calculator NEW
Hours and minutes to decimal hours for timesheets and payroll.
🔥 Coast FIRE Calculator NEW
The amount to invest today so growth alone funds your retirement.
🧮 Money Counter Calculator NEW
Count cash by denomination: total value plus bill and coin counts.
💱 Lakh to USD Converter NEW
Convert lakhs to US dollars for INR, PKR or BDT, with a custom-rate option.
⚖️ Alimony Calculator NEW
Estimate spousal support from both incomes and marriage length.
🏠 Mortgage Calculator
Monthly payment, total interest and lifetime cost of a home loan.
💰 Loan Calculator
Monthly payment and total interest for any amortizing loan.
🚗 Auto Loan Calculator
Monthly car payment from price, down payment and trade-in.
Financial Calculators NEW
Loans, mortgages, investing, taxes and everyday money math.
🛡️ Life Insurance Calculator
How much cover you need from income, debts and future costs.
📊 Balance Sheet Calculator
Assets, liabilities and net worth in one clean snapshot.
🧾 1099 Tax Calculator
SE tax, income tax and quarterly estimates for freelancers.
🔥 Coast FIRE Calculator
The amount to invest today so growth alone funds your retirement.
🧮 Money Counter Calculator
Count cash by denomination: total value plus bill and coin counts.
⚖️ Alimony Calculator
Estimate spousal support from both incomes and marriage length.
🏠 Mortgage Calculator
Monthly payment, total interest and lifetime cost of a home loan.
💰 Loan Calculator
Monthly payment and total interest for any amortizing loan.
🚗 Auto Loan Calculator
Monthly car payment from price, down payment and trade-in.
📈 Interest Calculator
Simple interest earned or owed over any time period.
🧾 Payment Calculator
What will the monthly payment be on any loan amount?
🏖️ Retirement Calculator
Project your savings at retirement age from monthly contributions.
📊 Amortization Calculator
Year-by-year schedule of principal vs interest on a loan.
💹 Investment Calculator
Future value of a lump sum plus regular contributions.
🏭 Inflation Calculator
What will money be worth after years of inflation?
⏳ Finance Calculator
Time value of money: grow a present value into the future.
🏛️ Income Tax Calculator
Estimate income tax for USA, UK, Pakistan, India, Canada and Australia.
💫 Compound Interest Calculator
Watch savings snowball with compounding and monthly deposits.
💼 Salary Calculator
Convert pay between hourly, weekly, monthly and annual.
📉 Interest Rate Calculator
What annual return turns your present sum into your goal?
🧾 Sales Tax Calculator
Add or extract sales tax / VAT from any price.
💵 Tip Calculator
Tip amount, total bill and fair split between diners.
🏷️ Discount Calculator
Sale price and savings from any discount percent.
📊 Profit Margin Calculator
Profit, margin and markup from cost and selling price.
💳 Debt Payoff Calculator
Compare snowball vs avalanche: which gets you debt-free faster?
🚗 Car Affordability Calculator
How much car can you afford based on your salary?
Fitness & Health Calculators
BMI, calories, body fat, pregnancy and training metrics.
⚖️ BMI Calculator
Body Mass Index from height and weight, with category.
🧒 Teen BMI Calculator
BMI percentile check for ages 13-19.
🔥 Calorie Calculator
Daily calorie needs (TDEE) from the Mifflin-St Jeor equation.
📏 Body Fat Calculator
Body fat percentage via the U.S. Navy tape-measure method.
🧬 BMR Calculator
Basal Metabolic Rate: calories burned at complete rest.
⚖️ Ideal Weight Calculator
Healthy weight range from four classic medical formulas.
🏃 Pace Calculator
Running pace and speed from distance and time.
👶 Pregnancy Calculator
Due date and current week from your last period.
💞 Pregnancy Conception Calculator
Estimate conception date from a known due date.
📅 Due Date Calculator
Due date from conception or IVF transfer date.
🍽 Macro Calculator
Daily protein, carb and fat targets for your goal.
🤰 Pregnancy Weight Gain Calculator
Healthy pregnancy weight gain range from pre-pregnancy BMI.
💪 Army Body Fat Calculator
Body fat percentage via the U.S. Army tape method.
🍞 Carbohydrate Calculator
Daily carb grams from calories and carb percentage.
🏋️ Lean Body Mass Calculator
Lean mass from weight and body fat percentage.
🎯 Healthy Weight Calculator
Healthy weight range for your height (BMI 18.5–24.9).
🏃 Calories Burned Calculator
Calories burned by activity, weight and duration.
🏆 One Rep Max Calculator
Estimate your 1-rep max with the Epley formula.
❤️ Target Heart Rate Calculator
Karvonen training zones from age and resting pulse.
🥚 Protein Calculator
Daily protein target from weight and activity.
Math Calculators
Percentages, fractions, geometry, statistics and more.
📍 Midpoint Calculator
The point exactly halfway between two points, with distance and slope.
✏️ Equation of a Line Calculator
Build a line equation from two points, a point and slope, or slope and intercept.
📏 Parallel & Perpendicular Line Calculator
Parallel and perpendicular lines through any point, with all three lines drawn.
🎯 Intercepts Calculator
Find where a line crosses the x and y axes, straight from standard form.
↗️ Tangent Line Calculator
Tangent and normal lines to any curve at a point, using exact derivatives.
🏹 Parabola Calculator
Vertex, focus, directrix and roots of a parabola, with a drawn graph.
🏈 Ellipse Calculator
Centre, foci, vertices, eccentricity and area of an ellipse.
🧲 Hyperbola Calculator
Vertices, foci and asymptotes of a hyperbola, with both branches drawn.
📐 Derivative Calculator
Differentiate any function symbolically — exact f′(x).
∫ Integral Calculator
Antiderivatives plus definite integrals with your bounds.
🧮 Equation Solver
Solve equations exactly or numerically, roots included.
📈 Graphing Calculator
Plot functions, zoom, trace values and build a table of values.
📊 T-Test Calculator
One-sample, two-sample and paired t-tests with p-values.
→ Limit Calculator
Limits of functions with left and right hand checks.
🔢 Scientific Calculator
Full scientific calculator: trig, logs, powers, factorials.
½ Fraction Calculator
Add, subtract, multiply and divide fractions, simplified.
% Percentage Calculator
Percent of a number, what-percent, and percent change.
🎲 Random Number Generator
Random integers in any range, with optional uniqueness.
△ Triangle Calculator
Area, perimeter and type from three side lengths.
σ Standard Deviation Calculator
Mean, variance and standard deviation of any dataset.
Converters NEW
Unit, numeral, code and measurement conversions.
💱 Lakh to USD Converter
Convert lakhs to US dollars for INR, PKR or BDT, with a custom-rate option.
⇄ Conversion Calculator
Convert length, weight and temperature units instantly.
🏛️ Roman Numeral Converter
Convert between integers and Roman numerals (1–3999).
🔐 Base64 Encode / Decode
Encode text to Base64 or decode it back, in your browser.
👟 Shoe Size Conversion
US to UK, EU and Japanese shoe sizes.
⬇️ Bandwidth Calculator
Download time from file size and connection speed.
🔗 URL Encode / Decode
Percent-encode URLs or decode them back to plain text.
💱 Crore to Lakh Converter
Convert crore to lakh instantly.
💱 Million to Lakh Converter
Convert millions to lakh instantly.
🔄 Million to Thousand Converter
Convert millions to thousands instantly.
🔄 Million to Billion Converter
Convert millions to billions instantly.
🔢 Number to Million Converter
Express any number in millions.
🔢 Number to Billion Converter
Express any number in billions.
💱 Crore to Million Converter
Convert crore to millions instantly.
🪙 Pennies to Dollars Calculator
Convert pennies to dollars and cents.
🔄 Square Feet to Acres Calculator
Free square feet to acres calculator: convert any square footage to acres instantly, plus.
🔄 Square Feet Converter
Free square feet converter: convert square feet to square meters, square inches, square.
🔄 Katha to Square Feet Converter
Free katha to square feet converter: convert katha to square feet and square meters using.
🔄 Acres to Square Feet Converter
Free acres to square feet converter: convert any acreage into square feet instantly.
🏡 Marla to Kanal Converter
Free marla to kanal converter for Pakistan land and property: 1 kanal = 20 marla, and 1.
Date & Time NEW
Age, dates, time zones, work hours and countdowns.
⏱️ Time to Decimal Calculator
Hours and minutes to decimal hours for timesheets and payroll.
🎂 Age Calculator
Exact age in years, months and days from a birthdate.
📆 Date Calculator
Days between dates, or add/subtract days from a date.
⏰ Time Calculator
Duration between times, or add/subtract time spans.
✅ Hours Calculator
Weekly work hours from daily clock-in / clock-out times.
🕒 Time Card Calculator
Weekly hours and overtime from daily totals.
🌍 Time Zone Calculator
Convert time between world time zones.
⏱️ Time Duration Calculator
Elapsed time between two times, even overnight.
📅 Day Counter
Exact days between any two dates.
🗓️ Day of the Week Calculator
Which weekday any date falls on.
Home & Auto
Construction projects, fuel, tires and household math.
🧱 Concrete Calculator
Concrete volume and bags needed for any slab.
🎨 Paint Calculator
How many gallons for your room? Includes doors & windows.
⛽ Fuel Cost Calculator
Trip fuel cost from distance, efficiency and price.
🛞 Tire Size Calculator
Tire diameter and circumference from size code.
🏠 Roofing Calculator
Roofing squares from dimensions and pitch.
❄️ BTU Calculator
Cooling power needed for any room size.
📐 Square Footage Calculator
Area from length and width in any unit.
🚗 Gas Mileage Calculator
MPG from miles driven and gallons used.
🐎 Horsepower Calculator
HP from torque and RPM.
🔧 Engine Horsepower Calculator
Rough HP estimate from engine displacement.
🪜 Stair Calculator
Riser count, tread depth and run from total rise.
💡 Electricity Calculator
Monthly kWh and cost of any appliance.
🛣️ Mileage Calculator
Distance from odometer readings.
🔲 Tile Calculator
Tiles needed for any floor size.
🌿 Mulch Calculator
How much mulch you need in cubic yards from bed size and depth.
🪨 Gravel Calculator
Cubic yards and tons of gravel for driveways and paths.
🧱 Square Feet to Cubic Yards Calculator
Free square feet to cubic yards calculator: enter area in square feet and depth in inches.
🧱 Square Yards Calculator
Free square yards calculator: enter length and width in feet to get the area in square.
🧱 Square Meter Calculator
Free square meter calculator: enter length and width in meters to get the area in square.
Science & Tech
Physics, chemistry, electrical and network calculations.
🌐 Subnet Calculator
Network, broadcast, mask and host range from IP + CIDR.
⚡ Ohm's Law Calculator
Solve V, I or R from any two values.
⚖️ Density Calculator
Density from mass and volume.
🔌 Resistor Calculator
Resistance value from 4-band color codes.
🏦 GDP Calculator
Gross domestic product via the expenditure approach.
⚡ Voltage Drop Calculator
Voltage drop over wire runs by gauge and distance.
⚖️ Mass Calculator
Convert weight in pounds to mass in kilograms.
🏋️ Weight Calculator
Weight force in newtons from mass (W = m×g).
🧪 Molarity Calculator
Solution concentration in mol/L from moles and volume.
⚗️ Molecular Weight Calculator
Molar mass in g/mol from a chemical formula.
🌍 Carbon Footprint Calculator
Free carbon footprint calculator: estimate your total yearly CO2 emissions from driving,.
Fun Tools
Games, lifestyle and just-for-fun calculators.
🎓 GPA Calculator
Semester GPA from course grades and credit hours.
📝 Grade Calculator
What final-exam score do you need for your target grade?
🔑 Password Generator
Strong random passwords with cryptographic randomness.
💘 Love Calculator
A playful compatibility score from two names.
📏 Height Calculator
Convert height between feet/inches and centimeters.
🎀 Bra Size Calculator
Band size and cup letter from two measurements.
🎲 Dice Roller
Roll any number of dice with any side count.
💨 Speed Calculator
Average speed from distance and time.
🌬 Wind Chill Calculator
Feels-like temperature from air temp and wind speed.
🌡 Heat Index Calculator
Feels-like heat from temperature and humidity.
💧 Dew Point Calculator
Dew point from temperature and humidity (Magnus formula).
⛳ Golf Handicap Calculator
Handicap index from scores, rating and slope (WHS-style).
😴 Sleep Calculator
Best bedtimes from your wake time using 90-min cycles.
🐱 Cat Age Calculator
Free cat age calculator: convert your cat's age into human-equivalent years and discover.
🐶 Dog Age Calculator
Free dog age calculator: convert dog years into human-equivalent years with smart.