How Much Paint or Stain for a Fence? (Fence Paint Calculator)
Work out how much paint or stain your fence needs: measure both sides, allow for rough timber, and turn it into litres or gallons with worked examples.
A fence soaks up far more paint than a smooth wall. Rough-sawn timber, gaps between boards and two sides to cover all push the number up, so a wall-paint estimate will leave you short.
Here's how to measure a fence properly and work out how much paint or stain to buy.
1. Measure the area
- Fence area = length × height.
- Painting both sides? Double it.
- Posts and rails on the back add roughly 10–15% if you paint them too.
- Picket fences: measure as if solid. The extra edges of each picket roughly make up for the gaps.
2. Use fence coverage, not wall coverage
| Surface | Typical coverage |
|---|---|
| Smooth planed timber | 300–400 sq ft/gal (8–10 m²/L) |
| Rough-sawn timber | 150–250 sq ft/gal (4–6 m²/L) |
| Old, dry, unpainted wood | Lower still for the first coat |
Always check the tin: fence paints and stains vary a lot.
Worked examples
- Imperial: a 50 ft fence, 6 ft high, both sides = 600 sq ft. Two coats at 200 sq ft/gal = 6 gallons. Add 10% = about 6.6 gallons, so buy one 5-gallon pail plus two 1-gallon cans.
- Metric: a 15 m fence, 1.8 m high, both sides = 54 m². Two coats at 6 m²/L = 18 L. Add 10% = about 20 L.
You can do the same in the paint calculator: enter the fence length as the length, its height as the wall height, width 0, no doors or windows, and set coverage to your fence paint's figure. (The calculator counts two opposite "walls" for each length, which is exactly both sides of the fence.)
Tips
- Spraying a fence is fast but can use 30–50% more paint than brushing.
- New pressure-treated timber often needs to weather for a few months before it takes paint.
- Pick a dry, overcast day: hot sun makes stain dry before it soaks in.