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Drywall Calculator: Panels, Tape, Compound and Fasteners
Work out how many drywall panels, how much joint tape and compound, and how many fasteners a wall needs — with the material rates and their source spelled out.
The estimator names no waste figure, so this one is yours to set. 0 % is a valid answer, not a placeholder.
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How the number is worked out
The steps from input to result
A wall is bought and hung in panels, in rolls of tape, in buckets of compound and in boxes of fasteners — not in square feet, so those are the four numbers that matter at the counter. Wall area divided by panel size gives the panel count; the same area, multiplied by a fixed rate, gives the tape, the compound and the fasteners. Everything else on this page exists to make those steps checkable.
The rates come from Lowe's "Drywall Materials Estimator and Coverage", retrieved 2026-08-28: one 4' × 8' panel per 32 ft², one 4' × 10' panel per 40 ft², one 4' × 12' panel per 48 ft², 0.35 ft of joint tape and 0.009 gal of joint compound per ft², and 2 nails or 1.25 screws per ft². Every one of these rates was checked against all 15 rows of the estimator's own table before use.
Joint compound is shown in gallons only, not in pounds. The estimator also lists a pound range for it, but only the top of that range follows the same rate consistently across the table — the bottom of the range does not reduce to one formula, and a made-up one would be worse than none. Where this calculator's gallon figure and the estimator's own table disagree, the difference is named below rather than smoothed over.
The formula
Written out, so you can check it by hand
Effective area = wall area × (1 + waste ÷ 100). Panels = round up(effective area ÷ panel size). Joint tape (ft) = effective area × 0.35. Joint compound (gal) = effective area × 0.009. Fasteners = round up(effective area × 2 for nails, or × 1.25 for screws).
Worked example
Worked with the preset values
A 200 ft² wall needs 200 ÷ 32 = 6.25 panels at 4' × 8', so 7 panels — a panel is not sold by the fraction. The same 200 ft² takes 200 × 0.35 = 70.0 ft of joint tape and 200 × 0.009 = 1.80 gal of joint compound, and at 2 nails per ft² that is 200 × 2 = 400 nails.
What this calculator does not do
Named, not left out
- 01Joint compound is shown in gallons only. The estimator's pound figure is a range (12–14 lb per 100 ft²) whose lower bound does not follow one consistent formula, so no pound figure is shown here.
- 02The gallon formula (area × 0.009) matches the estimator's own table at every size checked except one: at exactly 100 ft², this calculator shows 0.90 gal while the table itself lists 1.0 gal for that row. The formula is applied the same way at every size rather than special-cased for one.
- 03Only Lowe's "Drywall Materials Estimator and Coverage" is covered. Whether another retailer or manufacturer rates panels, tape, compound or fasteners the same way per square foot has not been checked.
- 04No waste allowance is preset, because the estimator names none. Cuts, damaged panels and irregular walls are yours to add as a percentage.
- 05This assumes standard panel thickness as used in the estimator's table. Panel thickness is not a variable of this calculator.
- 06Wall area is the net area you enter. Door and window openings are not subtracted automatically.
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Updated: 9/2/2026