Date & Time

Time Zone Converter

Convert time between major world time zones instantly. Plan international meetings and cal

Everyday

Speed Distance Time Calculator

Calculate speed, distance, or time from any two known values. Supports km/h, mph, and m/s.

Physics

Gravitational Potential Energy Calculator

Calculate gravitational potential energy using mass, gravity, and height. Essential physic

Finance

Break-Even Calculator

Calculate your break-even point in units and revenue. Know exactly when your business beco

Date & Time

Business Days Calculator

Count the number of working days between two dates, excluding weekends and optional public

Math

Fraction Calculator

Add, subtract, multiply and divide fractions. Get results in simplified form with step-by-

Pregnancy

Ovulation Calculator

Calculate your ovulation date and fertile window based on your last period and cycle lengt

Business

Break-Even Point Calculator

Calculate the break-even point in units and revenue for any product or business.

Ecology

Carbon Footprint Calculator

Estimate your personal carbon footprint from transportation, energy use, diet and lifestyl

Health

Calorie Calculator

Calculate your daily calorie needs (TDEE) based on age, weight, height and activity level.

Math

Quadratic Equation Solver

Enter coefficients a, b, and c to solve a quadratic equation and calculate its real roots.

Unit Converter

Length Converter

Convert between all length and distance units — meters, feet, inches, miles, kilometers an

Finance

BMR Calculator

Calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation for accurate

Math

Depreciation Calculator

Calculate annual depreciation of an asset using straight-line or declining balance methods

Math

Inflation Calculator

Calculate the impact of inflation on purchasing power and the equivalent future or past va

Finance

Protein Intake Calculator

Calculate your daily protein requirement based on body weight, activity level, and fitness

Chemistry

Stoichiometry Calculator

Calculate moles, mass, or molecules of reactants and products using stoichiometric ratios.

Everyday

Shoe Size Converter

Convert shoe sizes between US, UK, EU, and CM sizing systems for men and women.

Everyday

Power Consumption Calculator

Calculate total household power consumption in kWh and estimate monthly electricity bill f

Date & Time

Working Days Calculator

Calculate the number of working days between two dates, excluding weekends and optional pu

Everyday

Data Storage Converter

Convert between bytes, KB, MB, GB, TB and more. Essential for developers and IT profession

Finance

Calories Burned Swimming Calculator

Estimate calories burned during swimming based on stroke, duration, and body weight.

Everyday

Aspect Ratio Calculator

Calculate missing width or height from an aspect ratio, or find the ratio of any image or

Chemistry

Molarity Calculator

Calculate the molarity of a solution using moles of solute and volume in liters.

Physics

Torque Calculator

Calculate torque from force and lever arm length, or find force or distance given any two

Unit Converter

Weight Converter

Convert between kilograms, pounds, ounces, grams, stones and more weight units instantly.

Statistics

Standard Deviation Calculator

Calculate population and sample standard deviation, variance, and more for a dataset.

Finance

Calorie Intake Calculator

Calculate your recommended daily calorie intake for weight loss, maintenance, or weight ga

Pregnancy

Due Date Calculator

Calculate your pregnancy due date from last menstrual period (LMP) or conception date. See

Physics

Circular Motion Calculator

Calculate centripetal force, acceleration, velocity and period for an object in circular m

Physics

Friction Force Calculator

Calculate friction force and normal force using the coefficient of friction and object mas

Chemistry

Concentration Calculator

Calculate solution concentration in molarity, mass/volume percent, and parts per million (

Pregnancy

Blood Pressure Checker

Check your blood pressure reading and classify it as normal, elevated, or hypertensive bas

Unit Converter

Temperature Converter

Convert between Celsius, Fahrenheit, Kelvin and Rankine temperature scales instantly.

Chemistry

Empirical Formula Calculator

Find the empirical formula of a compound from the percentage composition of its elements.

Date & Time

Time Duration Calculator

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

Random

Password Generator

Generate strong, secure random passwords with custom length and character options.

Finance

Calorie Burned Calculator

Estimate calories burned during various exercises based on your weight, activity, and dura

Statistics

Mean Median Mode Calculator

Calculate mean, median, mode, range and standard deviation for a set of numbers.

Physics

Projectile Motion Calculator

Calculate range, max height, and time of flight for a projectile given initial velocity an

Physics

Force Calculator

Enter mass (kg) and acceleration (m/s²) to calculate the force in Newtons (N) based on New

Math

Pension Calculator

Estimate your retirement pension corpus and monthly income based on monthly contribution,

Construction

Concrete Volume Calculator

Calculate concrete volume in cubic metres and bags needed for slabs, columns, and footings

Math

Currency Exchange Calculator

Convert between major world currencies using customizable exchange rates.

Finance

Macro Nutrient Calculator

Calculate daily protein, carbohydrate, and fat targets based on your calorie goal and fitn

Math

Scientific Calculator

A fully functional scientific calculator with trigonometric, logarithmic, and advanced mat

Chemistry

Molarity Dilution Calculator

Calculate the volume or concentration needed to dilute a stock solution using C1V1 = C2V2.

Food

Recipe Calorie Calculator

Calculate total and per-serving calories by adding ingredients with their quantities.

Everyday

Cooking Measurement Converter

Convert between cups, tablespoons, teaspoons, milliliters, liters, ounces, and grams for c

Everyday

Unit Converter

Convert between common units of length, weight, temperature, and volume in one handy tool.

Chemistry

pH Calculator

Calculate the pH of a solution using the H⁺ ion concentration. Enter the concentration in

Pregnancy

Fertile Window Calculator

Calculate your fertile window and most likely ovulation date based on your cycle length.

Statistics

Z-Score Calculator

Calculate the Z-score of a data point and find the corresponding percentile rank.

Statistics

Confidence Interval Calculator

Calculate the confidence interval for a sample mean using sample size, standard deviation

Marine

Set and Drift Calculator

Calculate the set (direction) and drift (speed) of ocean current by comparing a vessel's D

Food

Baking Conversion Calculator

Convert common baking ingredient measurements between cups, tablespoons, teaspoons, grams

Marine

Dead Reckoning Calculator

Estimate a vessel's new position from a starting latitude/longitude, true course, speed an

Engineering

Voltage Drop Calculator

Calculate voltage drop and percentage drop across a cable run based on current, cable leng

Math

Slope Calculator

Calculate the slope, y-intercept, distance and equation of a line between two points (x1,

Marine

Rhumb Line Distance Calculator

Calculate rhumb line (loxodrome) distance and true course between two latitude/longitude p

Pregnancy

Conception Date Calculator

Estimate your likely conception date based on your last menstrual period (LMP) and average

Marine

Tidal Range Calculator

Calculate tidal range and mean tide level from high water and low water heights, and estim

Chemistry

Percent Yield Calculator

Calculate the percent yield of a chemical reaction from the actual yield and theoretical y

Science

Escape Velocity Calculator

Calculate the escape velocity needed to break free from the gravitational pull of a planet

Construction

Drywall Calculator

Calculate how many drywall sheets you need for a room based on wall dimensions, sheet size

Ecology

Household Water Usage Calculator

Estimate daily, weekly and annual household water usage based on showers, toilet flushes,

Marine

Compass Deviation Calculator

Convert between compass course and true course by applying magnetic variation and compass

Business

Employee Turnover Rate Calculator

Calculate employee turnover rate for a period based on the number of separations and the a

Math

Customer Lifetime Value Calculator

Calculate the Customer Lifetime Value (CLV) to understand the long-term revenue potential

Date & Time

Lunar Age Calculator

Calculate your age according to the traditional lunar calendar used in Chinese, Korean and

Food

Recipe Scaling Calculator

Scale any recipe up or down by adjusting servings and get all ingredient amounts recalcula

Pregnancy

Calorie Intake by Age Calculator

Find the recommended daily calorie intake for children, teens and adults based on age, gen

Ecology

Tree Planting CO2 Offset Calculator

Calculate how many trees you need to plant to offset your annual CO2 emissions.

Construction

Fence Calculator

Calculate the number of fence panels, posts and rails needed for any yard or property boun

Everyday

Number to Words Converter

Convert any number up to one trillion into words in English. Useful for cheques, invoices,

Math

Accounts Receivable Turnover Calculator

Calculate accounts receivable turnover ratio and average collection period to assess busin

Math

Average Revenue Per User Calculator

Calculate Average Revenue Per User (ARPU), MRR, ARR and revenue growth metrics for SaaS an

Chemistry

Buffer Solution pH Calculator

Calculate the pH of a buffer solution using the Henderson-Hasselbalch equation.

Math

Commission Calculator

Calculate sales commission, total earnings, commission rate, and net pay for any commissio

Math

Payroll Tax Calculator

Calculate gross pay, tax deductions, and net take-home pay for employees with adjustable t

Everyday

Exponent Calculator

Calculate exponents, powers, and roots. Supports any base and exponent including fractions

Business

Shipping Cost Calculator

Estimate shipping costs based on package weight, dimensions and shipping zone.

Marine

Seafarer Contract Calculator

Quickly find how many days are left in your seafarer contract, your completion date, and y

Pregnancy

Creatinine Clearance Calculator

Estimate kidney function (GFR) using the Cockcroft-Gault equation from age, weight, and se

Physics

Snell Law Calculator

Calculate the angle of refraction using Snell's Law when light passes between two media wi

Physics

Thermal Expansion Calculator

Calculate linear and volumetric thermal expansion of materials due to temperature change.

Chemistry

Redox Reaction Balancer Guide

Calculate the oxidation state of elements in common chemical compounds and ions.

Physics

Newton Second Law Calculator

Calculate force, mass or acceleration using Newton's Second Law (F = ma). Solve for any mi

Math

Churn Rate Calculator

Calculate monthly and annual customer churn rate, retention rate, and average customer lif

Construction

Tile Calculator

Calculate the number of tiles needed for any floor or wall area including waste factor.

Marine

Maritime Intercept Course Calculator

Calculate the precise course and time required to intercept another vessel using vector an

Everyday

Permutation and Combination Calculator

Calculate nPr (permutations) and nCr (combinations) for any values of n and r.

Everyday

Binary Calculator

Perform addition, subtraction, multiplication and division on binary numbers with step-by-

Math

Cost Per Unit Calculator

Calculate cost per unit, total production cost, and unit profit margin for manufacturing o

Finance

Pregnancy BMI Calculator

Calculate pre-pregnancy BMI and recommended weight gain range during pregnancy by trimeste

Everyday

Significant Figures Calculator

Round any number to a specified number of significant figures and identify sig figs in any

Construction

Concrete Mix Calculator

Calculate the ratio of cement, sand and gravel needed for different concrete mix grades an

Construction

Stair Calculator

Calculate stair dimensions including number of steps, riser height, tread depth and total

Everyday

IP Subnet Calculator

Calculate network address, broadcast address, host range, and number of hosts for any IPv4

Everyday

Statistical Probability Calculator

Calculate basic probability, complement, union and intersection of events from given outco

Finance

Hydration Tracker Calculator

Track your daily water intake and see how close you are to your hydration goal in real tim

Everyday

Numerology Calculator

Calculate your Life Path Number, Expression Number and Soul Urge Number based on your name

Everyday

Pool Volume Calculator

Calculate the volume of your swimming pool in gallons and liters based on shape and dimens

Pregnancy

Ovulation Calculator

Calculate your ovulation day and fertile window based on your last period date and cycle l

Finance

Retirement Savings Calculator

Calculate how much you will have saved by retirement based on current savings, monthly con

Marine

Gyro and Compass Error Calculator

Calculate gyro error, compass error, true course, magnetic course, and compass course from

Marine

Fresh Water Allowance Calculator

Professional multi-tab calculator for FWA, DWA, Draft Change, New Draft, Cargo Loading, an

Marine

Sea Service Calculator

Calculate your total sea service accurately from multiple sign-on and sign-off dates for c

Marine

Speed Converter

Convert between knots, km per hour, mph, and meters per second, with a vessel speed catego

Marine

Draft Survey Calculator

Complete draft survey calculator supporting initial, intermediate, and final surveys with

Marine

ETA Calculator

Precise estimated time of arrival calculations for your destination port based on distance

Marine

Anchor Swinging Radius Calculator

Determine the safe anchoring swing radius using vessel length overall, chain length paid o

Marine

TPC and TPI Calculator

Calculate Tons Per Centimeter (TPC) and Tons Per Inch (TPI) immersion for vessels from wat

Marine

Marine Bunker Fuel Consumption Calculator

Calculate marine bunker fuel consumption accurately for a single voyage or across a whole

Marine

Seafarer Salary Calculator

Calculate your monthly gross wage and total contract earnings from basic wage, fixed overt

Marine

Fuel & Bunker Calculator

Professional fuel and bunker calculator with four integrated tools: density correction to

Marine

Volume to Weight Converter

Convert cargo volume to weight and vice versa using cargo density or stowage factor, for c

Marine

Distance, Speed & Time Calculator

Calculate distance, speed, or time for any voyage leg, with an ETA mode, multi-leg passage

Marine

Distance Converter

Convert between nautical miles, kilometers, statute miles, fathoms, cables, meters, and fe

Marine

Arc to Time Converter

Convert arc measurements in degrees, minutes, and seconds to time in hours, minutes, and s

Marine

Mercator Sailing Course and Distance Calculator

Determine the true course and distance between two coordinates using Mercator sailing, acc

Marine

CPA and TCPA Calculator

Calculate Closest Point of Approach and Time to Closest Point of Approach from radar obser

Marine

Latitude Longitude Converter

Easily convert latitudes and longitudes between decimal degrees, degrees-minutes-seconds,

Marine

Maritime Currency Converter

Convert seafarer salaries across major currencies to compare contracts, calculate allotmen

Marine

True Wind Calculator

Convert a ship apparent wind reading into true wind speed and direction, useful for weathe

Marine

Wheel Over Point Calculator

Calculate the precise wheel over point for vessel course alterations, using turn radius or

Marine

Time to Arc Converter

Convert time values in hours, minutes, and seconds into arc degrees, minutes, and seconds

Marine

Plane Sailing Calculator

Calculate the course and distance between two points by modeling the Earth as a flat plane

Marine

Meridional Parts Calculator

Calculate meridional parts for any latitude, and reverse calculate latitude from a given m

Marine

Parallel Sailing Calculator

Calculate course and distance when sailing due East or West along a parallel of latitude,

Marine

Maritime Unit Converter

Real-time conversion across multiple maritime categories including speed, length, pressure

Marine

Great Circle Sailing Calculator

Calculate the shortest path distance and initial course between two points on the Earth su

Marine

Mercator Sailing Arrival Position Calculator

Swiftly discover your arrival coordinates given your departure position, course, speed and