Fence and deck projects

Deck stain calculator

Add the deck faces you plan to stain and measured railing or stair surfaces. Enter the selected stain’s coverage and coat schedule.

Your project measurements

A worked example is prefilled. Replace its values with your measurements and current product data.

Measure the deck surface between its edges.

Measure the deck surface between its edges.

Select only the broad deck faces that will receive stain.

Enter measured coated area for the faces and edges you will stain.

Enter measured tread, riser and stringer area you will stain.

Use the current label rate for your wood and application method.

Use the instructed coat count for this product and surface.

Optional allowance for your project. This is not a product recommendation.

Optional package volume for whole-container planning.

Your estimate

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Project notes

Understand this estimate

Deck stain quantity combines the selected deck faces with measured railing and stair surfaces, then applies the product coverage and coat schedule.

How to use the calculator

  1. Measure the deck footprint and faces

    Length × width gives one broad deck face. Select one or both faces that will be coated.

    Inputs Deck length · Deck width · Deck faces to stain

  2. Add measured railing and stair surfaces

    Count the coated faces and edges you intend to stain; these are entered areas rather than inferred opaque shapes.

    Inputs Railing and baluster area · Stair area

  3. Apply product coverage and purchase settings

    Use the current label rate and instructed coat count. Package size is optional.

    Inputs Product coverage · Coats · Extra allowance · Container size

Formula and variables

Deck area = length × width × selected faces. Total area = deck area + measured railing area + measured stair area. Gallons = total area ÷ coverage × coats × (1 + allowance ÷ 100).

L × W × FBroad deck area
Footprint multiplied by selected faces.ft²
R + SAdded surfaces
Measured railing and stair area.ft²
A ÷ C × NStain quantity
Total area divided by coverage and multiplied by coats.US gal

What the result means

Result interpretation

Stainable area is the combined entered surface. Gallons use one entered product rate and coat count; containers round upward when supplied. This does not infer opacity or area for open railings.

Limits and assumptions

This does not treat open railings as opaque surfaces. Measure balusters, rails and stairs that will be coated. If label coverage is for a complete system or multiple light coats, do not multiply it by the number of passes again.

Worked example

Deck top, railings and stairs

Assumptions
  • One 12 × 16 ft deck face is stained.
  • Railing and stair areas are measured as 40 and 18 ft².
  • Coverage is 200 ft²/US gal for one coat.
Calculation
  1. 12 × 16 + 40 + 18 = 250 ft².
  2. 250 ÷ 200 = 1.25 US gal; 1.25 ÷ 1 rounds up to 2 containers.
Expected result
Stainable deck area250 ft²
Stain estimate1.25 US gal
Whole containers2 containers

Common questions

Should I enter the deck footprint as railing area?
No. Enter the measured area of the railing faces and balusters you will coat.
Does the tool provide a stain coverage rate?
No. Enter the current rate for your product and surface from its label or technical data.

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Fence stain calculatorFence material calculator
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