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190 precision calculators for math, finance, health, and everyday life, all powered by a single BigNumber engine. No signup, no clutter, instant answers.

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190
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190 calculators
Math

Basic Calculator

Simple everyday arithmetic: add, subtract, multiply, divide with a retro LCD display.

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LCD
Math

Scientific Calculator

Advanced scientific calculator with trigonometry, logarithms, powers, and constants.

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LCD
Math

Percentage Calculator

Calculate percentages: what is X% of Y, percentage change, and more.

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Math

Fraction Calculator

Add, subtract, multiply, divide fractions. Simplify and convert to decimals.

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Math

Area Calculator

Calculate area of rectangles, circles, triangles, trapezoids, and ellipses.

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Math

Volume Calculator

Calculate volume of cubes, spheres, cylinders, cones, and pyramids.

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Math

Quadratic Equation Solver

Solve ax² + bx + c = 0. Find roots, discriminant, and vertex.

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Math

Statistics Calculator

Calculate mean, median, mode, standard deviation, and variance from a data set.

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Math

GCD & LCM Calculator

Find the Greatest Common Divisor and Least Common Multiple of two or more numbers.

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Math

Number Base Converter

Convert between binary, octal, decimal, and hexadecimal number systems.

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Math

Exponent Calculator

Calculate powers, roots, and exponential expressions.

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Math

Permutation & Combination

Calculate permutations (nPr) and combinations (nCr) with factorial support.

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Math

Ratio Calculator

Simplify ratios, find equivalent ratios, and solve proportions.

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Math

Logarithm Calculator

Calculate natural log (ln), common log (log₁₀), and log with custom base.

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Math

Pythagorean Theorem Calculator

Find the missing side of a right triangle using a² + b² = c².

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Math

Circle Calculator

Calculate circle area, circumference, diameter, and radius from any known value.

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Math

Triangle Calculator

Calculate area, angles, and sides of any triangle using various formulas.

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Math

Prime Factorization Calculator

Find prime factors of any number and check if a number is prime.

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Math

Rounding Calculator

Round numbers to nearest integer, decimal places, or significant figures.

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Math

Scientific Notation Calculator

Convert to and from scientific notation (e.g., 3.5 × 10⁴).

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Math

Standard Deviation Calculator

Calculate population and sample standard deviation with step-by-step breakdown.

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Math

Mean, Median, Mode Calculator

Find the mean, median, mode, and range of any data set instantly.

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Math

Z-Score Calculator

Calculate z-scores and find probabilities for normal distributions.

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Math

Confidence Interval Calculator

Calculate confidence intervals for means and proportions.

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Math

Probability Calculator

Calculate probability of events, combinations, and conditional probability.

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Finance

Loan EMI Calculator

Calculate monthly EMI, total interest, and payment schedule for any loan.

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Finance

Compound Interest Calculator

Calculate compound interest with flexible compounding frequencies.

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Finance

Simple Interest Calculator

Calculate simple interest: I = P × R × T.

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Finance

SIP Calculator

Systematic Investment Plan calculator: project your wealth growth over time.

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Finance

Tip Calculator

Calculate tip amount and split bills between multiple people.

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Finance

Discount Calculator

Calculate discount amount, final price, and savings.

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Finance

Profit Margin Calculator

Calculate gross profit margin, net margin, and markup percentage.

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Finance

ROI Calculator

Calculate Return on Investment with gain/loss analysis.

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Finance

Salary Calculator

Convert between hourly, daily, weekly, monthly, and annual salary.

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Finance

Mortgage Calculator

Calculate monthly mortgage payments, total interest, and amortization.

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Finance

Inflation Calculator

Calculate the effect of inflation on purchasing power over time.

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Finance

Break-Even Calculator

Find the break-even point: units and revenue needed to cover costs.

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Finance

Savings Goal Calculator

How much to save monthly to reach your financial goal.

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Finance

Currency Converter

Convert between major world currencies with real-time exchange rates.

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Finance

Auto Loan Calculator

Calculate monthly auto loan payments, total interest, and affordability.

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Finance

Credit Card Payoff Calculator

Find out how long it will take to pay off your credit card debt.

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Finance

Debt-to-Income Ratio Calculator

Calculate your debt-to-income ratio to assess loan eligibility.

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Finance

Refinance Calculator

Compare your current mortgage with a refinanced loan to see potential savings.

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Finance

Rent vs. Buy Calculator

Compare the costs of renting versus buying a home over time.

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Finance

Present Value Calculator

Calculate the present value of future cash flows and investments.

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Finance

Future Value Calculator

Calculate the future value of investments and savings with compound interest.

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Finance

Annuity Calculator

Calculate annuity payments, present value, and future value of annuities.

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Finance

Retirement Calculator

Estimate how much you need to save for a comfortable retirement.

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Finance

401(k) Calculator

Project your 401(k) balance at retirement with employer matching.

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Finance

Sales Tax Calculator

Calculate sales tax and total price for any purchase amount.

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Finance

Commission Calculator

Calculate sales commission based on rate and tiered structures.

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Finance

APR Calculator

Calculate the Annual Percentage Rate for loans and credit products.

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Finance

Depreciation Calculator

Calculate straight-line and declining balance depreciation schedules.

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Finance

Gold Price Calculator

Check real-time gold prices and calculate value of gold by weight and purity.

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Finance

Crypto Converter

Convert between cryptocurrencies and fiat with real-time market rates.

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Health & Fitness

BMI Calculator

Calculate Body Mass Index with health category classification.

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Health & Fitness

Calorie & TDEE Calculator

Calculate your Basal Metabolic Rate and Total Daily Energy Expenditure.

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Health & Fitness

Body Fat Calculator

Estimate body fat percentage using the US Navy method.

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Health & Fitness

Ideal Weight Calculator

Find your ideal weight range using multiple scientific formulas.

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Health & Fitness

Water Intake Calculator

Calculate daily water intake based on weight, activity, and climate.

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Health & Fitness

Heart Rate Zone Calculator

Calculate your target heart rate zones for optimal training.

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Health & Fitness

Macronutrient Calculator

Calculate daily protein, carbs, and fat intake based on your goals.

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Health & Fitness

Pregnancy Due Date Calculator

Estimate pregnancy due date and track trimester milestones.

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Health & Fitness

BMR Calculator

Calculate your Basal Metabolic Rate using Mifflin-St Jeor equation.

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Health & Fitness

TDEE Calculator

Calculate Total Daily Energy Expenditure based on activity level.

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Health & Fitness

One Rep Max Calculator

Estimate your one-rep max using various lifting formulas.

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Health & Fitness

Ovulation Calculator

Predict your fertile window and ovulation date based on cycle length.

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Health & Fitness

BAC Calculator

Estimate Blood Alcohol Content based on drinks, weight, and time.

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Health & Fitness

Running Pace Calculator

Calculate running pace, split times, and race finish predictions.

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Health & Fitness

Protein Calculator

Calculate daily protein needs based on weight, activity, and goals.

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Health & Fitness

Carbohydrate Calculator

Calculate daily carbohydrate needs based on diet type and activity.

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Health & Fitness

Lean Body Mass Calculator

Estimate your lean body mass and body fat percentage.

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Health & Fitness

Body Surface Area Calculator

Calculate body surface area using Du Bois and Mosteller formulas.

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Health & Fitness

GFR Calculator

Estimate Glomerular Filtration Rate for kidney function assessment.

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Health & Fitness

Pregnancy Weight Gain Calculator

Track healthy weight gain during pregnancy by trimester.

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Health & Fitness

Conception Calculator

Estimate conception date and fertile window based on due date or LMP.

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Health & Fitness

Period Calculator

Track menstrual cycle, predict next period, and identify fertile days.

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Date & Time

Age Calculator

Calculate exact age in years, months, and days from your birth date.

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Date & Time

Date Difference Calculator

Find the exact difference between two dates in days, weeks, months, and years.

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Date & Time

Time Calculator

Add or subtract hours, minutes, and seconds.

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Date & Time

Countdown Calculator

Count days until a future event: birthday, holiday, deadline.

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Date & Time

Day of the Week Calculator

Find out what day of the week any date falls on.

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Date & Time

Time Zone Converter

Convert times between different time zones around the world.

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Date & Time

Time Duration Calculator

Calculate the duration between two times in hours, minutes, and seconds.

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Date & Time

Hours Calculator

Calculate total hours worked and overtime from clock-in and clock-out times.

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Date & Time

Date Calculator

Add or subtract days, weeks, months, or years from any date.

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Date & Time

Day Counter

Count the number of days between two dates including or excluding weekends.

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Date & Time

Sleep Calculator

Calculate optimal bedtime and wake-up time based on sleep cycles.

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Date & Time

Time Card Calculator

Calculate weekly time card totals, regular hours, and overtime pay.

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Conversion

Length Converter

Convert between meters, feet, inches, miles, kilometers, and more.

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Conversion

Weight Converter

Convert between kilograms, pounds, ounces, grams, and stones.

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Conversion

Temperature Converter

Convert between Celsius, Fahrenheit, and Kelvin.

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Conversion

Speed Converter

Convert between km/h, mph, m/s, knots, and more.

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Conversion

Data Storage Converter

Convert between bytes, KB, MB, GB, TB, and PB.

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Conversion

Energy Converter

Convert between joules, calories, kWh, BTU, and more.

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Conversion

Cooking Converter

Convert between cups, tablespoons, teaspoons, ml, liters, and ounces.

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Conversion

Pressure Converter

Convert between pascal, bar, psi, atm, and torr.

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Conversion

Angle Converter

Convert between degrees, radians, gradians, and turns.

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Conversion

Power Converter

Convert between watts, horsepower, kilowatts, and BTU/hr.

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Conversion

Fuel Converter

Convert between MPG, L/100km, km/L, and other fuel economy units.

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Conversion

Roman Numeral Converter

Convert between Arabic numbers and Roman numerals.

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Everyday Tools

GPA Calculator

Calculate your Grade Point Average from courses and credits.

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Everyday Tools

Random Number Generator

Generate random numbers within a specified range.

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LCD
Everyday Tools

Password Generator

Generate strong, secure passwords with customizable options.

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Everyday Tools

Word & Character Counter

Count words, characters, sentences, and paragraphs in your text.

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Everyday Tools

Color Converter

Convert between HEX, RGB, and HSL color formats with live preview.

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Everyday Tools

Grade Calculator

Calculate weighted grades and final course averages.

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Everyday Tools

URL Encode / Decode

Encode and decode URLs and query parameters safely.

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Everyday Tools

Base64 Encode / Decode

Encode text to Base64 or decode Base64 back to text.

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Everyday Tools

IP Subnet Calculator

Calculate subnet masks, network addresses, and host ranges from IP and CIDR.

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Everyday Tools

Height Converter

Convert between feet/inches and centimeters.

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Everyday Tools

Shoe Size Converter

Convert shoe sizes between US, UK, EU, and CM measurements.

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Everyday Tools

Love Calculator

A fun compatibility calculator based on names and birth dates.

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Islamic

Zakat Calculator

Calculate your annual Zakat obligation on cash, gold, silver, and investments.

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Islamic

Prayer Times Calculator

Get accurate prayer times (Fajr, Dhuhr, Asr, Maghrib, Isha) for any location.

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Islamic

Hijri Date Converter

Convert between Gregorian and Hijri (Islamic) calendar dates.

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Islamic

Islamic Inheritance Calculator

Calculate shares of inheritance according to Islamic law (Sharia).

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Islamic

Qibla Direction Calculator

Find the Qibla direction (Kaaba bearing) from any location on Earth.

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Islamic

Ramadan Calendar

View Ramadan dates, fasting times, and Iftar/Suhoor schedules.

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Islamic

Tahajjud Calculator

Calculate the best time for Tahajjud (night prayer) based on local prayer times.

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Islamic

Hajj & Umrah Dates

View upcoming Hajj and Umrah dates in both Hijri and Gregorian calendars.

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Construction

Concrete Calculator

Calculate concrete volume, bags needed, and cost for slabs, footings, and columns.

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Construction

Tile Calculator

Calculate number of tiles needed and total cost for flooring and walls.

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Construction

Gravel Calculator

Calculate gravel volume and weight needed for driveways, paths, and gardens.

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Construction

Mulch Calculator

Calculate mulch volume and bags needed for garden beds and landscaping.

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Construction

Roofing Calculator

Estimate roofing materials, shingles, and cost based on roof dimensions.

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Construction

Stair Calculator

Calculate stair dimensions, rise, run, and stringer length for safe stair design.

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Construction

Paint Calculator

Estimate paint quantity and cost for walls, ceilings, and exterior surfaces.

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Construction

Square Footage Calculator

Calculate square footage of rooms, houses, and irregular shapes.

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Construction

Drywall Calculator

Estimate drywall sheets, mud, tape, and screws needed for a project.

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Construction

Flooring Calculator

Calculate flooring material needed including waste factor for various floor types.

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Engineering

Ohm's Law Calculator

Calculate voltage, current, resistance, and power using Ohm's Law.

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Engineering

Resistor Calculator

Calculate resistor values from color bands and vice versa.

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Engineering

Bandwidth Calculator

Calculate download/upload time, data transfer, and internet speed needs.

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Engineering

Voltage Drop Calculator

Calculate voltage drop in electrical cables based on length and gauge.

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Engineering

Horsepower Calculator

Convert between mechanical, metric, and electrical horsepower.

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Engineering

Density Calculator

Calculate density, mass, and volume of materials and substances.

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Engineering

Molarity Calculator

Calculate molarity, molality, and solution concentration for chemistry.

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Engineering

Propeller Tip Speed Calculator

Calculate propeller or fan tip speed and Mach number.

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Other

Dice Roller

Roll virtual dice with various sides and modifiers for games and probability.

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Other

Fuel Cost Calculator

Calculate fuel cost for a trip based on distance, MPG, and gas price.

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Other

BTU Calculator

Calculate BTU requirements for heating and cooling rooms and buildings.

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Other

Wind Chill Calculator

Calculate the feels-like temperature based on wind speed and air temperature.

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Other

Dew Point Calculator

Calculate dew point and relative humidity from temperature and humidity data.

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Other

Heat Index Calculator

Calculate the heat index (feels-like temperature) from temperature and humidity.

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Other

Golf Handicap Calculator

Calculate your golf handicap index from recent scores and course ratings.

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Other

Tire Size Calculator

Compare tire sizes and calculate speedometer error when changing tire size.

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Other

Gas Mileage Calculator

Calculate MPG, fuel efficiency, and cost per mile for your vehicle.

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Other

Bill Splitter

Split restaurant bills evenly or by item among multiple people.

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Other

Molecular Weight Calculator

Calculate molecular weight of chemical compounds from their formulas.

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Other

Weather Calculator

Get current weather and calculate weather-related metrics for any city.

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Geometry

Polygon Area Calculator

Calculate area of regular polygons: pentagon, hexagon, octagon, and more.

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Geometry

Ellipse Calculator

Calculate area, circumference, and focal points of an ellipse.

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Geometry

Sphere Calculator

Calculate volume, surface area, and diameter of a sphere.

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Geometry

Cylinder Calculator

Calculate volume, surface area, and lateral area of a cylinder.

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Geometry

Cone Calculator

Calculate volume, surface area, and slant height of a cone.

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Geometry

Pyramid Calculator

Calculate volume and surface area of square and triangular pyramids.

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Geometry

Parallelogram Calculator

Calculate area, perimeter, and diagonals of a parallelogram.

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Geometry

Trapezoid Calculator

Calculate area, perimeter, and median of a trapezoid.

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Geometry

Circle Sector Calculator

Calculate area, arc length, and chord length of a circle sector.

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Geometry

Circle Segment Calculator

Calculate area and arc length of a circle segment.

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Geometry

2D Distance Calculator

Calculate distance between two points in a 2D plane.

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Geometry

3D Distance Calculator

Calculate distance between two points in 3D space.

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Geometry

Midpoint Calculator

Find the midpoint between two points in 2D or 3D space.

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Statistics

Correlation Calculator

Calculate Pearson correlation coefficient between two data sets.

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Statistics

Linear Regression

Calculate linear regression line, slope, intercept, and R².

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Statistics

Binomial Distribution

Calculate binomial probabilities, mean, variance, and standard deviation.

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Statistics

Normal Distribution

Calculate probabilities, z-scores, and percentiles for normal distributions.

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Statistics

Poisson Distribution

Calculate Poisson probabilities for rare events.

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Statistics

Chi-Square Calculator

Calculate chi-square statistic for contingency tables and goodness of fit.

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Statistics

T-Test Calculator

Perform one-sample and two-sample t-tests.

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Statistics

ANOVA Calculator

Calculate one-way ANOVA: F-statistic, sum of squares, and p-value estimate.

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Statistics

Outlier Calculator

Detect outliers using IQR method and Z-score method.

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Statistics

Percentile Calculator

Calculate percentiles, quartiles, and deciles for any data set.

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Statistics

Effect Size Calculator

Calculate Cohen's d and other effect size measures.

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Statistics

Sample Size Calculator

Calculate required sample size for surveys and experiments.

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Statistics

Histogram Calculator

Calculate bin widths, frequencies, and generate histogram data.

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Trigonometry

Sin Cos Tan Calculator

Calculate sine, cosine, and tangent for any angle in degrees or radians.

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Trigonometry

Inverse Trig Calculator

Calculate arcsin, arccos, arctan, and other inverse trig functions.

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Trigonometry

Unit Circle Calculator

Find coordinates and trig values for any angle on the unit circle.

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Trigonometry

Law of Sines Calculator

Solve triangles using the Law of Sines: a/sin(A) = b/sin(B) = c/sin(C).

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Trigonometry

Law of Cosines Calculator

Solve triangles using the Law of Cosines: c² = a² + b² - 2ab cos(C).

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Trigonometry

Trig Identity Verifier

Verify and simplify common trigonometric identities.

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Trigonometry

Polar ↔ Rectangular

Convert between polar coordinates (r,θ) and rectangular coordinates (x,y).

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Trigonometry

Degrees ↔ Radians

Convert angles between degrees, radians, and gradians.

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Trigonometry

Trig Function Evaluator

Evaluate sin, cos, tan, sec, csc, cot for any angle with full working.

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Trigonometry

Reference Angle Calculator

Find the reference angle for any angle in standard position.

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Trigonometry

Coterminal Angle Calculator

Find positive and negative coterminal angles for any given angle.

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Trigonometry

Trig Equation Solver

Solve basic trigonometric equations like sin(x) = a, cos(x) = b.

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Trigonometry

Hyperbolic Functions

Calculate sinh, cosh, tanh, and their inverses.

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