Utility Calculators
Our utility calculators handle the everyday conversions and counting tasks that come up at work and at home, including date and time differences, unit conversions, and number base translations. They are fast, precise, and ready whenever you need a quick answer.
Age Calculator
Calculate exact age in years, months, and days from a date of birth.
Agricultural Tank Mix & Spray Calibration Calculator
Calculate nozzle flow rates, product amounts per tank, acres per load, and W-A-L-E-S mixing order for agricultural spray applications.
Aquarium Volume Calculator
Find the gallons and liters a rectangular fish tank holds from its dimensions.
Aspect Ratio Calculator
Resize images to a fixed aspect ratio and simplify any width-to-height ratio.
Bandwidth Calculator
Calculate how long a file takes to transfer at a given connection speed.
Base64 Encode/Decode
Encode text to Base64 or decode Base64 back to text.
Battery Storage ROI Calculator
Calculate return on investment for home battery storage with TOU arbitrage, solar pairing, degradation modeling, and demand charge reduction.
Bra Size Calculator
Calculate bra size from band and bust measurements.
Brick Calculator
Calculate bricks needed for a wall or patio.
BTU Calculator
Calculate BTU requirements for heating or cooling a room.
Cat Age Calculator
Convert cat years to human years.
Coin Flipper
Flip a virtual coin — heads or tails.
Color Contrast Ratio Calculator
Check the WCAG contrast ratio between two colors and whether it meets AA and AAA.
Concrete Calculator
Calculate how much concrete you need for slabs, footings, and columns.
Conversion Calculator
Convert between units of length, weight, temperature, volume, and more.
Cooking Measurement Converter
Convert cups, tablespoons, teaspoons, millilitres and ounces, plus cups to grams by ingredient.
Countdown Calculator
Count down to a future date with a live days, hours, minutes and seconds breakdown.
Date Calculator
Add or subtract days, months, and years from any date.
Day Counter
Count the number of days between two dates or until a future date.
Day of the Week Calculator
Find what day of the week any date falls on.
Deck Footing & Framing Calculator (IRC)
Calculate footing sizes, beam spans, joist sizing, and material takeoff for residential decks per IRC span tables and soil bearing capacity.
Density Calculator
Calculate density, mass, or volume using the density formula.
Dew Point Calculator
Calculate the dew point from temperature and relative humidity.
Dice Roller
Roll virtual dice with customizable sides and number of dice.
Dog Age Calculator
Convert dog years to human years using modern formulas.
DPI Print Size Calculator
Convert between image pixels and physical print size at any DPI resolution.
Drive Time Calculator
Calculate estimated drive time from distance and speed.
Drywall Calculator
Calculate drywall sheets needed for a room.
Electric Bill Calculator
Estimate a full monthly electricity bill with tiered rates, fixed charges and tax.
Electricity Calculator
Calculate electricity cost from appliance wattage and usage hours.
Engine Horsepower Calculator
Estimate engine horsepower from quarter-mile time and vehicle weight.
EV vs Gas Savings Calculator
Compare the annual fuel cost of an electric car versus a gas car and find the breakeven point.
Fence Calculator
Calculate materials needed for a fence.
Force Calculator
Calculate force, mass, or acceleration using F = ma.
Friction Calculator
Calculate static and kinetic friction forces.
Fuel Cost Calculator
Calculate fuel cost for a trip based on distance, fuel efficiency, and gas price.
Gas Mileage Calculator
Calculate your vehicle fuel efficiency in MPG or L/100km.
GDP Calculator
Calculate Gross Domestic Product using the expenditure approach (C + I + G + net exports).
Golf Handicap Calculator
Calculate your golf handicap index from recent round scores.
GPA Calculator
Calculate your GPA from course grades and credit hours.
Grade Calculator
Calculate your current grade and what you need on the final exam.
Gravel Calculator
Calculate how much gravel or aggregate you need by volume and weight.
Half-Life Calculator
Calculate radioactive decay and the remaining quantity using the half-life formula.
Heat Index Calculator
Calculate the heat index (feels-like temperature) from temperature and humidity.
Heat Pump vs Gas Furnace Lifecycle Calculator
Compare lifecycle costs of an air-source heat pump against a gas furnace with COP-temperature modeling and degree-day energy integration.
Height Calculator
Predict a child's adult height from the parents' heights.
Hex to RGB Color Converter
Convert hex color codes to RGB values and back, with 3-digit shorthand support.
Horsepower Calculator
Calculate horsepower from torque and RPM.
Hours Calculator
Calculate the hours and minutes between a start time and an end time.
Image File Size Calculator
Estimate the file size of an image from its dimensions, color depth, and compression.
IP Subnet Calculator
Calculate IP subnets, CIDR ranges, network addresses, and host ranges.
Kinetic Energy Calculator
Calculate kinetic energy using KE = ½mv².
LED Savings Calculator
Calculate savings from switching to LED bulbs.
Love Calculator
A fun calculator that generates a compatibility score from two names.
Mass Calculator
Convert mass between kilograms, grams, milligrams, pounds, ounces, and tons.
Meeting Cost Calculator
Calculate the cost of a meeting based on attendees and salaries.
Mileage Calculator
Calculate mileage reimbursement based on distance and IRS standard rates.
Molarity Calculator
Calculate molarity, moles, or volume for solutions.
Molecular Weight Calculator
Calculate the molecular weight (molar mass) of chemical compounds.
Momentum Calculator
Calculate linear momentum using p = mv.
Mulch Calculator
Calculate how much mulch you need for a garden bed or landscape area.
Ohm's Law Calculator
Calculate voltage, current, resistance, or power using Ohm's law.
Paint Calculator
Calculate how much paint you need for a room.
Password Generator
Generate secure random passwords with customizable length and character types.
Plumbing DWV Pipe Sizing Calculator
Size drain, waste, and vent pipes per IPC/UPC codes using drainage fixture unit (DFU) table lookups and slope-based calculations.
Pool Volume Calculator
Calculate the volume of a swimming pool in gallons.
Potential Energy Calculator
Calculate gravitational potential energy using PE = mgh.
PPI Calculator
Calculate the pixel density (PPI) of any screen from its resolution and diagonal size.
Propane Tank Usage Calculator
Estimate propane burn time and the fuel remaining in a tank from its weight.
Reading Time Calculator
Calculate how long it takes to read or speak a text.
Relief Valve Sizing Calculator (API 520/521)
Size pressure relief valves per API 520/521 for gas, liquid, steam, and two-phase service with API 526 standard orifice selection.
Resistor Calculator
Decode a 4-band resistor color code into its resistance value and tolerance.
Roofing Calculator
Calculate roofing materials needed based on roof dimensions and pitch.
Shoe Size Conversion
Convert shoe sizes between US, UK, and EU sizing systems.
Sleep Calculator
Calculate optimal bedtime or wake time based on sleep cycles.
Speed Calculator
Calculate speed, distance, or time using the formula speed = distance / time.
Square Footage Calculator
Calculate the square footage of a rectangular room, floor, or lot.
Stair Calculator
Calculate stair dimensions including rise, run, and number of steps.
Tile Calculator
Calculate how many tiles you need for a floor or wall area.
Time Calculator
Add and subtract hours, minutes, and seconds.
Time Card Calculator
Calculate weekly work hours and pay from time card entries.
Time Duration Calculator
Calculate the duration between two date-times in years, months, days, hours, and minutes.
Time Zone Calculator
Convert times between common time zones and calculate the offset difference.
Tip Calculator
Calculate tip amount and split the bill among multiple people.
Tire Size Calculator
Find a tire’s diameter, circumference, sidewall height, and revolutions per mile from its size code.
Typing Speed Calculator
Calculate typing speed in words per minute, with net WPM after errors and typing accuracy.
Unit Converter
Convert between units of length, weight, temperature, volume, and speed.
Unit Price Calculator
Find the cost per unit and compare two package sizes to see which is the better deal.
URL Encode/Decode
Encode or decode URLs and query string parameters using percent-encoding.
Video Bitrate Calculator
Estimate video file size from bitrate and duration, or the bitrate needed for a target size.
Voltage Divider Calculator
Calculate the output voltage and current of a resistive voltage divider circuit.
Voltage Drop Calculator
Calculate voltage drop in electrical wiring based on wire gauge, length, and load.
Wallpaper Calculator
Estimate how many wallpaper rolls a wall needs, accounting for pattern repeat waste.
Wavelength Calculator
Calculate wavelength, frequency, or wave speed using v = fλ.
Weight Calculator
Convert between weight and mass units such as pounds, kilograms, stone, ounces, grams, and tons.
Whole-House Electrification Cost Planner
Model cumulative electrical loads, IRA incentives, and 15-year total cost of ownership for switching from gas to all-electric appliances.
Wind Chill Calculator
Calculate the wind chill factor from temperature and wind speed.
Word Counter
Count words, characters, sentences, and paragraphs.
Work & Energy Calculator
Calculate the work done by a force acting over a distance at any angle.