Calculator library

Find the right calculator.

Choose a category or browse the full library. Each tool is designed with clear units, beginner-friendly presets, and optional advanced settings.

Power & Backup Towing & Trailers Home & Basement Workshop & Tools Materials & Projects Geometry Basics

Project cost estimators

For remodeling budgets, use the project cost estimator section. It estimates planning ranges for bathrooms, basements, decks, painting, flooring, kitchens, roofs, tile showers, and drywall repairs.

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Search calculators

Type a project, material, or problem, such as deck, square footage, battery, roof, paint, concrete, insulation, or extension cord.

Power & Backup

5 calculators

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Home Generator Size

Estimate the generator size needed for essential home backup loads during a power outage.

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Camping & RV Generator

Estimate generator wattage for RV, camping, cabin, and outdoor power needs.

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Power Station Runtime

Estimate how long a portable power station can run common devices.

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Battery Runtime

Estimate battery runtime from watt-hours, 12V amp-hours, device watts, and usable capacity.

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Extension Cord Voltage Drop

Estimate extension cord voltage drop from one-way cord length, amps, voltage, and AWG wire gauge.

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Towing & Trailers

2 calculators

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Towing & Trailers

Trailer Payload

Estimate remaining trailer payload after trailer weight, cargo, and reserve margin.

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Towing & Trailers

Tongue Weight

Estimate target trailer tongue weight from loaded trailer weight and tongue-weight percentage.

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Home & Basement

10 calculators

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Home & Basement

Dehumidifier Size

Estimate dehumidifier capacity for basements, crawlspaces, and damp rooms from room dimensions and dampness level.

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Home & Basement

Garage Heater BTU

Estimate heater BTU needs for a garage, shop, or workspace.

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Home & Basement

Sump Pump Size

Estimate sump pump flow requirement based on water inflow and lift height.

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Home & Basement

Water Softener Size

Estimate water softener grain capacity from household size and water hardness.

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Home & Basement

Mini Split BTU

Estimate mini split BTU size from room dimensions, ceiling height, and room conditions.

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Home & Basement

Aquarium Volume

Estimate aquarium volume from inside length, width, and water height.

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Home & Basement

Firewood Cords

Estimate full cords of stacked firewood from pile dimensions.

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Home & Basement

Insulation Calculator

Estimate insulation packages from area dimensions, package coverage, and waste allowance.

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Home & Basement

Wall Assembly R-Value

Estimate whole-wall R-value including wall dimensions, cavity insulation, wood studs, drywall, sheathing, and continuous foam insulation.

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Home & Basement

Bathroom Fan CFM

Estimate bathroom exhaust fan CFM from room size and air-change target.

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Workshop & Tools

3 calculators

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Workshop & Tools

Air Compressor CFM

Estimate air compressor CFM needed for common air tools.

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Workshop & Tools

Pressure Washer Time

Estimate cleaning time from surface dimensions, pressure washer cleaning rate, and setup time.

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Workshop & Tools

Dust Collector CFM

Estimate dust collector airflow needs for common woodworking machines.

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Materials & Projects

17 calculators

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Materials & Projects

Concrete Bags

Estimate how many concrete bags you need from slab length, width, thickness, bag yield, and waste allowance.

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Materials & Projects

Gravel Calculator

Estimate gravel volume and tonnage from length, width, and depth.

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Materials & Projects

Paint Calculator

Estimate paint needed from room dimensions, coats, coverage, openings, and overage.

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Materials & Projects

Mulch Calculator

Estimate mulch volume from bed length, width, and depth.

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Materials & Projects

Topsoil Calculator

Estimate topsoil volume from area and depth.

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Materials & Projects

Tile Calculator

Estimate tile quantity from project dimensions, tile size, and waste percentage.

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Materials & Projects

Flooring Calculator

Estimate flooring boxes from room dimensions, waste, and box coverage.

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Materials & Projects

Fence Materials

Estimate fence posts, sections, and rail length from total fence length and spacing.

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Materials & Projects

Deck Boards

Estimate deck board count from deck size, board width, gap, length, and waste.

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Materials & Projects

Drywall Sheets

Estimate drywall sheets from surface dimensions, sheet size, and waste allowance.

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Materials & Projects

Paver Base

Estimate compacted gravel base and bedding sand for patios and walkways.

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Materials & Projects

Shingle Bundles

Estimate roof shingles and bundles from building footprint, roof pitch, bundle coverage, overhang, extra roof areas, and waste allowance.

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Materials & Projects

Caulk Tubes

Estimate caulk tubes from joint length, joint width, joint depth, and tube size.

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Materials & Projects

Board Feet

Calculate board feet from board thickness, width, length, and quantity.

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Materials & Projects

Stud Count

Estimate the number of wall studs needed based on wall length, stud spacing, corners, and openings.

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Materials & Projects

Stair Stringer

Estimate stair riser count, actual riser height, tread count, and horizontal run.

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Materials & Projects

Roofing Underlayment

Estimate roofing underlayment rolls from building footprint, roof pitch, roll coverage, overlap, and waste.

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Geometry Basics

9 calculators

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Geometry Basics

Square Footage

Calculate square footage or square meters for rooms, floors, walls, slabs, yards, and project areas from length and width.

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Geometry Basics

Rectangle Area

Find the area of a rectangle from length and width, with imperial and metric support.

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Geometry Basics

Triangle Area

Calculate triangle area from base and height, with imperial and metric units.

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Geometry Basics

Right Triangle

Calculate hypotenuse, area, perimeter, and angles from the two legs of a right triangle.

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Geometry Basics

Pythagorean Theorem

Find the diagonal side of a right triangle from two square sides.

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Geometry Basics

Circle Area

Calculate circle area, circumference, and diameter from radius.

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Geometry Basics

Trapezoid Area

Calculate trapezoid area from the two parallel bases and height.

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Geometry Basics

Cylinder Volume

Calculate cylinder volume from radius and height, with cubic feet, cubic meters, gallons, and liters.

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Geometry Basics

Roof Pitch

Calculate roof pitch, slope angle, and slope factor from rise and run.

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