Deck Stain Calculator — Estimate Stain & Supplies

Quickly calculate how much stain you need for your deck project

Feet (ft)
Meters (m)
Measure the longest side of your deck
Measure the width perpendicular to the length
Advanced Options (Railings, Steps, Balusters) +
Total length of all railings
Height from top to bottom of railing
Total number of balusters (vertical posts)
Width of each baluster
Total number of steps on your deck
Width of each step
Depth (tread) of each step
Typical range: 150-300 sq ft per gallon. Lower for porous wood, higher for smooth surfaces.
Optional: for cost estimation

Your Stain Estimate

0
Total Gallons Needed
Total Surface Area 0 sq ft
Gallons per Coat 0
Number of Coats 2
Waste Factor 0%
Estimated Cost –
Estimate rounded up to the nearest container. Coverage varies — check product label.

Shopping List

0
5-Gallon Containers
Most cost-effective for larger projects
0
1-Gallon Containers
Good for smaller areas or touch-ups
Show Calculation Details +

Detailed calculation breakdown will appear here.

How to Measure Your Deck

Follow these steps to accurately measure your deck for staining:

Step 1: Measure Deck Floor

Measure the length and width of each rectangular section of your deck. Multiply length by width to get the area of each section, then add them together for the total deck floor area.

Step 2: Measure Railings

Measure the total length of all railings around your deck. Then measure the height from top to bottom. Multiply length by height to get the total railing surface area.

Step 3: Measure Balusters

Count all the balusters (vertical posts between railings). Measure the width of a typical baluster and multiply by the railing height to get the surface area of one baluster. Multiply by the total number of balusters.

Step 4: Measure Steps

Count the number of steps. Measure the width and depth (tread) of a typical step. Multiply width by depth to get the area of one step, then multiply by the number of steps.

Formula: Total Surface Area = Deck Floor + Railings + Balusters + Steps

Frequently Asked Questions

How many square feet does one gallon of stain cover? +

Coverage varies by product and wood porosity. We use a default of 175 ft² per gallon per coat; typical range is 150–300 ft²/gal. More porous wood will require more stain, while smooth, sealed surfaces will require less.

Should I buy more than the calculator shows? +

Yes, we recommend enabling the “+10% waste” option to account for spillage, application variations, and touch-ups. It’s better to have a little extra than to run out mid-project, especially since stain colors can vary between batches.

How do I measure railings and balusters? +

Measure rail length × height for rails; count balusters and measure each’s width or use spacing per foot. For railings, measure the total linear feet of railing and multiply by the height. For balusters, count all vertical posts and multiply count by width and height.

What’s the difference between stain types? +

Transparent stains show wood grain but offer minimal protection. Semi-transparent stains add some color while allowing grain to show through. Semi-solid stains provide more color with moderate grain visibility. Solid stains offer full color coverage and maximum protection but hide the wood grain.

How many coats should I apply? +

Most professionals recommend 2 coats for optimal protection and appearance. One coat may be sufficient for maintenance coats on previously stained decks in good condition. Three coats might be needed for very porous wood or when changing colors significantly.

Test Harness (Development Only)

Use these test cases to validate calculator functionality: