Drywall Calculator
Free drywall calculator. Work out wall and ceiling area from room dimensions, deduct your doors and windows, and get the sheets, screws, joint compound, and joint tape to buy with an adjustable waste allowance. Imperial and metric, 100% client-side.
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What is Drywall Calculator?
The Drywall Calculator is a free, browser-based tool that turns a room measurement into a drywall material list. Enter the room length, width, and wall height and it derives the wall perimeter and surface area, adds the ceiling if you are boarding it, deducts the doors and windows you are not covering, applies a waste allowance, and returns the number of drywall sheets, screws, joint compound, and joint tape to buy. Choose a sheet size from 4 × 8 up to 4 × 12 ft or switch to metric board, set the waste percentage, and adjust every consumption rate so the estimate matches the board and compound you actually buy. Both square feet and square meters are shown, and the formula panel repeats the arithmetic with your own numbers so nothing has to be taken on trust. All math runs 100% client-side - no sign-up, no uploads, and it keeps working offline on site.
Key Benefits
- Wall area from perimeter × height, so the surface area never has to be worked out by hand
- Door and window openings deducted at their real size instead of a guessed percentage
- Standard sheet sizes for both imperial and metric board, plus a custom width and length
- Screws, joint compound, and joint tape with the rate that produced each number on show
- Full formula panel with your own figures substituted, plus ft² and m² side by side
- 100% client-side and offline-capable - your room dimensions stay on your device
Common Use Cases
- •Building a material list for a basement or garage board-out before calling the supplier
- •Checking a contractor drywall quote against your own takeoff
- •Estimating screws, compound, and tape as a separate line from the sheets
- •Comparing a 4 × 8 sheet layout against 4 × 12 sheets to cut down on joints
- •Switching a room measurement between feet and metres for a metric supplier
How to Use the Drywall Calculator
- Measure the room: Measure the room length, room width, and wall height with a tape measure. Pick Imperial (feet) or Metric (meters) to match your tape, then leave the ceiling switch on if you are boarding the ceiling as well as the walls.
- Deduct the openings: Enter the count, width, and height of the doors and windows that will not be boarded. Each group is deducted as count × width × height from the wall area, so a 3 × 7 ft door removes 21 ft² of board.
- Choose the sheet and waste allowance: Pick a standard sheet size such as 4 × 8 ft, or switch to Custom and type your own width and length. Set the waste allowance — 10% for a simple room, 15% when there are many openings or the board runs diagonally.
- Read and copy the material list: The calculator returns the sheets to buy, the screws and boxes, the joint compound and containers, and the joint tape and rolls. Every rate behind those numbers is editable, and the formula panel shows the arithmetic with your own figures so you can check it by hand.
Key Features
- Walls, optional ceiling, and deducted door and window openings in one estimate
- Standard sheet sizes: 4 × 8, 4 × 9, 4 × 10, or 4 × 12 ft, or metric board from 1.2 × 2.4 to 1.2 × 3.6 m
- Adjustable waste allowance, 10% by default, applied to the sheet count
- Screws with boxes, joint compound with containers, and joint tape with rolls
- Every consumption rate is editable and shown next to the number it produced
- Full formula panel with your own numbers substituted, plus ft² and m² side by side