A fence has more surface than its outline suggests: board-on-board and shadow-box fences have overlapping and edge surfaces, while open picket and split-rail fences have much less. Rough-sawn cedar and dry weathered wood absorb far more stain than smooth new boards, so use the lower coverage figure for those.
How to use the Fence Stain Calculator
- Fence length
- Fence height
- Fence style
- Sides
- Coats
- Coverage
- Price
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the fence length and height, choose the style, sides, coats, product coverage and price.
Tips for an accurate estimate
- Keep units consistent – the calculator handles conversions, but check every field’s unit before reading a result.
- Use values from standards, data sheets or test pieces whenever you have them; typical values are only a starting point.
- Apply appropriate safety factors and have structural, electrical and pressure work checked by a qualified professional.
- Record the inputs you used so the calculation can be reviewed later.
Common mistakes to avoid
- Confusing diameter and radius, or nominal and actual sizes.
- Using allowable stresses and ultimate strengths interchangeably.
- Treating rule-of-thumb results as a substitute for code tables or an engineered design.
Inputs explained
| Field | What to enter |
|---|---|
| Fence length | Units: ft, m, in, yd, cm |
| Fence height | Units: ft, m, in, yd, cm |
| Fence style | Choose one: Solid privacy (factor 1.0), Board-on-board (1.2), Shadow box (1.3), Picket with gaps (0.7) … |
| Sides | Choose one: Both sides, One side |
| Coats | A number |
| Coverage | Choose one: Solid stain – 200 ft²/gal, Semi-transparent – 250 ft²/gal, Clear sealer – 300 ft²/gal, Rough-sawn / weathered – 150 ft²/gal |
| Price | Units: /US gal, /L |
What each result means
- Area to stain = [Fence length]×[Fence height]×[Fence style]×[Sides]
- Stain needed = [Area to stain]×[Coats]÷[Coverage]
- 1-gallon cans = ceil([Stain needed]÷0.003785411784 – 0.000001)
- 5-gallon pails = ceil([Stain needed]÷0.01892705892 – 0.000001)
- Cost (1-gallon cans) = [1-gallon cans]×0.003785411784×[Price]
Example values
How the main result changes when Fence length changes and everything else stays at the example values above:
| Fence length (ft) | Stain needed (US gal) |
|---|---|
| 75 | 4.5 |
| 112.5 | 6.75 |
| 150 | 9 |
| 187.5 | 11.25 |
| 225 | 13.5 |
| 300 | 18 |
Formula
Area = length × height × style factor × sidesGallons = area × coats ÷ coverageWorked example
Inputs — Fence length: 150 ft; Fence height: 6 ft; Fence style: Solid privacy (factor 1.0); Sides: Both sides; Coats: 1; Coverage: Solid stain – 200 ft²/gal; Price: $35 /US gal.
Results — Area to stain = 1,800 ft²; Stain needed = 9 US gal; 1-gallon cans = 9; 5-gallon pails = 2; Cost (1-gallon cans) = $315.00.
Frequently asked questions
How much stain for a 6 ft privacy fence?
Each 100 ft of fence has 1,200 ft² of surface on both sides – about 6 gallons per coat at 200 ft²/gal.
Should I spray or brush fence stain?
Spraying is fast; back-brushing afterwards works the stain into the wood and evens the colour.
How often should a fence be stained?
Every 2–3 years for semi-transparent stains, 4–5 for solid colour.
What formula does the Fence Stain Calculator use?
Area = length × height × style factor × sides.