Other Calculators

More than just years - calculate your exact age down to the second! Find out what day you were born, days until your next birthday, and fun age facts.

Work out cement bags, mix ratios for concrete and mortar, and material costs. Includes mix design, curing timeline, and project planning tools.

A genuinely free, untimed IQ test: 36 generated questions across pattern, sequence, spatial and verbal reasoning, scored as an honest range with your percentile — no email, no paywall.

Interactive periodic table of all 118 elements with names, symbols, atomic mass, charges and electron configuration. Colour the table by any property and open any element for full detail.

Calculate work hours, overtime, and pay from time clock entries. Track daily hours, calculate overtime pay, and manage multiple time entries with our free time tracking calculator.

Simplify payroll with automatic overtime calculations. Track multiple weeks, handle breaks, night shifts, and export timesheets. Perfect for freelancers and HR departments.

Asphalt tonnage from area and compacted depth. Hot-mix runs about 145 lb per cubic foot, so a cubic yard is just under two tons.

Calculate network bandwidth requirements and data transfer rates.

Estimate battery runtime in hours from capacity (mAh or Wh) and device current draw.

Calculate bra size based on measurements and sizing charts.

Calculate BTU requirements for heating and cooling systems.

Estimate your annual carbon footprint from transportation, home energy, and lifestyle, with tips to reduce emissions.

Estimate carpet needed for a room in square yards or meters, including padding and waste allowance, with cost estimates.

Convert °C to °F with the exact formula (°C × 9/5 + 32) and a weather table.

Convert centimeters to feet and inches, with a height table from 150 to 200 cm.

Convert centimeters to inches: cm ÷ 2.54, with a reference table and height examples.

Compost in cubic yards and bags from bed size and depth. Only 300-700 lb per cubic yard dry, so order by volume rather than weight.

Calculate concrete volume, bags needed, and material costs for projects.

Convert between various units of measurement and currencies.

A language-free IQ test: patterns, sequences and spatial rotation only, so vocabulary and cultural knowledge never move your score.

Calculate file transfer time for any bandwidth in Mbps, Gbps, or MB/s. Plan downloads, uploads, and data migrations.

Calculate differences between dates and add/subtract days from dates.

Count days between dates and calculate day numbers.

Find what day of the week any date falls on.

Decomposed granite by area and depth. DG runs about 1.7 tons per cubic yard — the heaviest common landscape material, and far heavier than it looks.

Calculate density using mass and volume for physics and chemistry.

Calculate dew point temperature from humidity and temperature.

Roll virtual dice with various sides for games and probability.

Calculate drywall sheets and screws needed by wall and ceiling area, with waste factor and 4x8 or 4x12 board sizes.

Calculate electrical power, energy consumption, and utility costs.

Calculate electricity costs from kWh usage and your local rate, with appliance-by-appliance cost breakdowns.

Calculate engine horsepower based on displacement, RPM, and efficiency.

Convert feet to meters: feet × 0.3048 (exact), with a reference table.

Fill dirt in cubic yards and tons from area and depth. Loose fill is about 2,000 lb per yard and compacted reaches 2,600 — both are shown.

Work out exactly what score you need on the final exam to reach the course grade you want, and see what each possible final score would leave you with.

Calculate flooring needed in square feet or meters across multiple rooms, with waste factor for hardwood, tile, vinyl, and laminate.

Calculate fuel costs for trips based on distance, MPG, and gas prices.

Calculate fuel efficiency, MPG, and gas consumption for vehicles.

Calculate Gross Domestic Product and economic indicators.

Calculate golf handicap index and course handicap for golfers.

Calculate GPA (Grade Point Average) for high school and college students.

Calculate final grades, weighted grades, and grade requirements.

Calculate gravel needed for driveways, paths, and construction projects.

Calculate heat index and apparent temperature in hot weather.

Calculate horsepower, torque, and engine power specifications.

Calculate hours worked, time differences, and hourly calculations.

Convert inches to centimeters: inches × 2.54, with a reference table.

Estimate download and upload speeds, convert Mbps to MB/s, and check what bandwidth your online activities need.

Calculate IP subnets, CIDR notation, and network addressing.

Convert any IQ score to its exact percentile and rarity, on the right scale — Wechsler SD 15, old Stanford–Binet SD 16, or Cattell SD 24.

Age-tiered reasoning tests for ages 4–7, 8–12 and 13–17 — visual puzzles, no reading needed for younger children, results framed honestly for parents.

Convert kilograms to pounds: kg ÷ 0.45359237 (exact), with a body-weight table.

Convert kilometers to miles: km ÷ 1.609344 (exact), with running-distance examples.

Convert pounds to kilograms: lbs × 0.45359237 (exact), with a reference table.

Crushed limestone by area and depth in cubic yards, tons and bags — about 1.45 tons per cubic yard, from washed clean stone to crusher run.

Fun love compatibility calculator based on names and birthdates.

Calculate mass using density and volume or force and acceleration.

Convert meters to feet: divide by 0.3048 (exact), with a reference table.

Calculate mileage, travel distance, and reimbursement for business travel.

Convert millimeters to inches: mm ÷ 25.4, with fractional-inch equivalents.

Calculate molarity, moles, and solution concentrations for chemistry.

Calculate molecular weight and molar mass of chemical compounds.

Calculate mulch needed for landscaping projects by area and depth.

Calculate voltage, current, resistance, and power using Ohms Law.

Estimate paint needed in gallons or liters from wall area, number of coats, and coverage rate, accounting for doors and windows.

Generate secure passwords with customizable length and character sets.

Estimate how long a brute-force attack would take to crack your password, with entropy in bits and strength recommendations.

Calculate swimming pool volume in gallons or liters for rectangular, round, and oval pools.

A 12-question IQ estimate in about five minutes, honest about its wide margin — with a path to the full test for a tighter range.

Calculate resistor values, color codes, and electrical resistance.

River rock in cubic yards, tons and bags — 1.4 to 1.75 tons per cubic yard, with larger stone weighing less per yard.

Convert between Arabic numbers and Roman numerals.

Calculate roofing materials, shingles needed, and roofing costs.

Calculate sand by area and depth in cubic yards, tons and bags — including the dry-versus-wet density range that shifts the tonnage by about a quarter.

Convert uptime percentages (99.9%, 99.99%) into allowed downtime per day, month, and year for SLA planning.

Convert shoe sizes between US, UK, EU, and other international standards.

Calculate optimal sleep and wake times based on sleep cycles.

Size a solar panel system from your monthly electricity usage. Estimate panels needed, system cost, payback period, and savings.

Calculate speed, velocity, and convert between speed units.

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

Calculate stair dimensions, rise, run, and building code compliance.

Calculate theoretical yield, percent yield, and limiting reactants for chemical reactions.

Calculate tiles needed for flooring and wall projects with waste factor.

Add, subtract, and calculate time durations in hours, minutes, and seconds.

Calculate work hours, overtime, and payroll from time cards.

Calculate time duration between two times or dates.

Convert time between different time zones around the world.

Calculate tips, split bills, and total costs for restaurant dining.

Calculate tire dimensions, plus sizing, and tire comparisons.

Work out how much topsoil you need in cubic yards, tons and bags from the bed size and depth, with the density range that moisture actually causes.

Convert between units of length, weight, temperature, volume, area, and speed.

Calculate voltage drop in electrical circuits and wire sizing.

Calculate weight and convert between different weight units.

Add your homework, quiz, midterm and exam categories with their weights to get your current course grade — and see how much each category is really moving it.

Calculate wind chill temperature and apparent temperature.

Calculate the correct wire gauge for electrical circuits using ampacity, voltage drop, and NEC guidelines.