Deck Stain Calculator
A 12 by 16 floor, 40 ft of railing at 3 ft on both faces, and the stair faces add to 455.00 ft². Two coats at the example 200 ft² per gallon are 4.55 gal.
Last updated . The deck job is selected. Coverage starts at 200, labeled as an example. Coats start at 2. No price.
A deck stain calculator for the floor, the railings, and the stairs, or a fence stain calculator for length × height × the sides you stain. Gallons are the stained square feet multiplied by the coat count, then divided by coverage you type.
Boards and joists: deck calculator. House paint, not deck stain: paint calculator. Fence posts and pickets: fence material calculator.
Deck or fence stain
200 is sitting in the coverage box so this gallon line can be checked. Read the number printed on the can. Railing faces open at 2. Fence sides open at 2. Stair faces are the tread tops and the riser fronts.
Results
How the stained area becomes gallons
The floor is length × width. Railings are the linear feet times the height times the number of faces. Stairs are the stair width times the sum of the tread tops and the riser fronts: tread count × tread depth, plus riser count × riser height. A fence replaces all three with length × height × sides. Gallons equal the total times the coat count, divided by the square feet per gallon you type. The result is shown to two decimals. It is not rounded up to a whole can.
Faces and sides start at 2. Change them when only one side is stained. The coverage box starts at 200 so the opening gallon line has a divisor. That 200 is an example for checking the arithmetic. Read the can and replace it. An empty coverage box keeps the areas and asks you to enter a coverage. No can price is stored here.
Gallons for the opening jobs
| Case | Area | Coats | Coverage | Gallons |
|---|---|---|---|---|
| Deck floor 192, railings 240, stairs 23 | 455.00 ft² | 2 | 200 | 4.55 gal |
| Fence 80 × 6, two sides | 960.00 ft² | 2 | 200 | 9.60 gal |
Worked example
Leave the deck job, 12 by 16, railing 40 by 3 with 2 faces, stairs 3 ft wide with 5 treads at 10 in and 6 risers at 7 in, 2 coats, and coverage 200. Total area reads 455.00 ft² · 42.27 m². Gallons reads 4.55 gal.
Deck and fence stain questions
How many gallons does the opening deck take?
Leave Job on Deck, rails, and stairs, floor 12 ft by 16 ft, railing 40 ft by 3 ft with 2 faces, stair width 3 ft, 5 treads at 10 in, 6 risers at 7 in, coats 2, and coverage 200. Floor or fence reads 192.00 ft² · 17.84 m². Railings reads 240.00 ft² · 22.30 m². Stairs reads 23.00 ft² · 2.14 m². Total area reads 455.00 ft² · 42.27 m². Gallons reads 4.55 gal.
Where does 4.55 come from?
The floor is 12 × 16 = 192. Both railing faces are 40 × 3 × 2 = 240. Stairs are 3 × (5 × 10/12 + 6 × 7/12) = 3 × (4.1666… + 3.5) = 23. The total is 455. Two coats are 910 square feet. At 200 square feet per gallon, 910 ÷ 200 = 4.55. The gallon line is that quotient, not a rounded-up can count.
How many gallons for an 80 ft fence at 6 ft, both sides?
Set Job to Fence and leave length 80 ft, height 6 ft, sides 2, coats 2, and coverage 200. Floor or fence reads 960.00 ft² · 89.19 m². Railings reads —. Stairs reads —. Total area reads 960.00 ft² · 89.19 m². Gallons reads 9.60 gal. The fence area is 80 × 6 × 2 = 960, and 960 × 2 ÷ 200 = 9.60.
What if the coverage box is empty?
Clear coverage and leave the deck filled in. Floor, railings, stairs, and total area still show. Gallons reads: Enter a coverage. The 200 in that box is an example so the division can be checked. Replace it with the square feet printed on the can. This page does not claim a brand covers 200.
Are both railing faces and both fence sides required?
No. Railing faces starts at 2 and fence sides starts at 2 because a board usually has two faces. Set either one to 1 when you stain a single face. Stair area is the tread tops plus the riser fronts, one time each, times the stair width. It is not doubled.
What does a blank coat count or a zero area say?
Clear the coat count. The note reads: Enter a coat count greater than zero. On a fence, clear the length. The note reads: Enter a fence length, a height, and at least one side. Zero out the deck floor, the railing, and the stairs. The note reads: The stained area is zero. Enter a floor, a railing, a stair, or a fence.
Does this page count the deck boards or the stain price?
Neither. Board count and joists are the deck calculator. A price per gallon is not on this form. You type coverage, and the result is gallons. Pickets and posts live on the fence material calculator. Stain gallons are the only output here.