Household
Household Calculators
51 calculators
Sizing and running-cost estimates for home equipment: room-size matching, appliance wattage and energy use, battery runtime, burn times and fixture sizing. Most of these derive from a manufacturer's rated figure applied to your dimensions, so a room that is not rectangular or a device that is not new will drift from the estimate.
- Air Purifier Room Size Calculator Find the CADR an air purifier needs for your room and how large a purifier that rating covers.
- Appliance Wattage Calculator Find the typical wattage of a household appliance and what it costs to run.
- Battery Life Calculator — mAh and Current Draw Enter capacity in mAh, current draw in mA and usable capacity percentage. Estimate battery runtime in hours and days for a constant-current load.
- Bed Size Calculator Compare mattress sizes in inches and centimetres and see how much floor space each one leaves in your room.
- Candle Burn Time Calculator Estimate candle burn time from net wax weight and a user-measured wax consumption rate.
- Ceiling Fan Size Calculator Pick the right ceiling fan blade span for a room based on its floor area.
- Cord of Wood Calculator Convert a stack into full cords and face cords, with the cut length shown in the estimate.
- Cost of Baby Calculator Estimate a baby’s first-year costs from diapers, your own feeding and childcare budgets, gear and extra monthly costs.
- Curtain Length Calculator Find the exact curtain drop for sill, apron, floor and puddle length hangings.
- Curtain Size Calculator Calculate the panel width and length for curtains, including the fullness needed for a gathered look.
- Data Usage Calculator Estimate monthly internet data from streaming, gaming, browsing and downloads.
- Date Calculator — Add or Subtract Add or subtract days, weeks, calendar months or years. See the resulting date, weekday and elapsed days, with month-end and leap-year handling.
- Dehumidifier Size Calculator Explore a simplified dehumidifier capacity estimate from room area, dampness and temperature. Compare the model with rated equipment and ENERGY STAR guidance.
- Diaper Calculator Estimate diaper use and cost using editable planning assumptions. Actual use varies by child, product and routine; the estimate is not medical advice.
- Dilution Ratio Calculator Work out how much concentrate and water you need for any dilution ratio and final volume.
- Drip Faucet Calculator See how much water a dripping tap wastes and what it costs you over a year.
- Electricity Cost Calculator Calculate what any appliance costs to run per day, month and year.
- Firewood Calculator Estimate how many cords of firewood you will burn in a heating season.
- Flooring Calculator Calculate the floor area, waste allowance and number of boxes or cartons of flooring you need.
- Furniture Spacing Calculator Find the recommended gap between pieces of furniture for seating, coffee tables and traffic lanes.
- Generator Wattage Calculator Add up running watts and starting watts for the appliances you want to back up and size a generator.
- Grout Calculator Calculate how much grout a tiling job needs from the tile size, joint width and joint depth.
- Hair Growth Calculator See how long your hair will be after a given time, or how long it takes to reach a target length.
- Hammock Hang Calculator Find the right hanging height and distance for a comfortable 30-degree hammock hang.
- Hot Tub Chemical Calculator Calculate sanitizer and pH doses for a hot tub based on its water volume.
- Hot Tub Cost Calculator Estimate what it costs to heat and run a hot tub over a month and a year.
- Ice Melt Calculator Estimate ice melt quantity from area, the rate on your product label and bag size. Calculate required product weight and whole bags for a driveway or walkway.
- Attic Insulation Calculator — Area, Thickness and Cost Enter attic length and width, target R-value and material R per inch. Estimate coverage area with waste, thickness in inches and material cost in USD.
- LED Savings Calculator Compare the running cost of incandescent or halogen bulbs with LED replacements and see the annual saving.
- Lighting Calculator Calculate how many lumens and bulbs a room needs based on its size and how bright the space should be.
- Lumens to Watts Converter Convert a light output in lumens to the wattage you need for each bulb technology.
- Patio Heater BTU Calculator Estimate outdoor patio heater output and fuel use from area, ceiling height and temperature rise.
- Pool Water Adjustment Planner Estimate free-chlorine demand and alkalinity adjustment without guessing a product or pH dose.
- Pool Salt Calculator Find how many pounds of salt a saltwater pool needs to reach its target salinity.
- Pool Volume Calculator Calculate the water volume of a rectangular, round or oval pool in gallons and litres.
- Quit Smoking Savings Calculator See how much money you save by quitting smoking and how much life expectancy is regained.
- Room Layout Calculator Check the clearances in a room and find the largest furniture footprint that still leaves comfortable walkways.
- Rug Size Calculator Find the right rug dimensions for a living room, dining room or bedroom based on the furniture layout.
- Shelving Weight Capacity Calculator Estimate the safe load a shelf can carry from its span, thickness and material.
- Shower Cost Calculator Find what each shower costs in water and energy, and what the habit adds up to over a year.
- Smoke Detector Placement Calculator Work out how many smoke detectors a home needs and where they should go.
- Snow Removal Cost Calculator Estimate the cost of snow removal for a driveway or lot by area and snowfall depth.
- Sunscreen Calculator — Amount and Reapplication Estimate a sunscreen amount per application and a simple reapplication schedule.
- Tattoo Size Calculator Convert a tattoo size into area, session time and a price estimate.
- Tile Calculator Work out how many tiles you need for a floor or wall, including the cut allowance.
- Toilet Paper Calculator Calculate how many rolls of toilet paper a household uses and what it costs per year.
- TV Mounting Height Calculator Find the right height to mount a TV so the centre of the screen sits at a comfortable viewing angle.
- TV Size Calculator Estimate screen dimensions from seating distance and a selected viewing angle reference.
- Household Water Use Calculator Estimate five selected direct household water uses; indirect and unmodeled uses are excluded.
- Water Usage Calculator Estimate your household water use from showers, toilets, laundry and outdoor watering.
- Window Blind Size Calculator Calculate the correct blind width and drop for inside or outside mounting.
No calculators match your search.
Household planning usually begins with a measured room, an equipment rating or a repeated use. Keep these inputs separate: floor area does not by itself determine every equipment requirement, and rated power does not tell you how many hours a device runs. Choose a tool with the inputs you can actually provide.
Plan rooms and material quantities
Measure the relevant length, width or volume before estimating flooring, wallpaper or pool contents. Allowances and package sizes belong to the particular product and installation; a geometric quantity alone is not a final purchase list.
Compare usage and running costs
Combine power and operating time for an electricity-cost scenario, or model water use and battery runtime with their own inputs. Room-equipment estimates have additional assumptions about the space and conditions.
Separate planning from installation
Verify actual product dimensions, ratings and instructions before using an estimate to buy or install equipment. Structural loads, combustion equipment, chemical treatment and electrical work need checks beyond the simple models on these pages.