Calculate Plot Area + Perimeter from Dimensions

A seller says the lot is “100 × 200 feet.” You multiply, get 20,000 sq ft, and move on. But how many acres is that? What’s the perimeter if you need a fence quote? And what happens to your budget if the listing was in meters and you assumed feet? A plot area calculator that handles dimensions, perimeter, and unit conversion in one pass saves you from exactly that kind of slip. Enter length and width, pick your unit, and the tool returns area in sq ft, acres, hectares, marla, and kanal—plus perimeter and a quick fencing/cost scenario so you can reality-check a deal before you call anyone.

The result is a planning number, not a legal survey. It tells you whether a lot is roughly the size you need, what fencing might run, and how the price per sq ft compares across listings. For anything that goes into a contract or a permit application, you still need a licensed surveyor to pin the corners and confirm the boundary.

• Mixing feet and meters in the same calculation. A 30 m × 20 m lot is 6,458 sq ft. If you accidentally type 30 × 20 with the unit set to feet, you get 600 sq ft—a ten-fold undercount. Always double-check the unit dropdown before reading the result.
• Treating gross area as buildable area. Setbacks, easements, and drainage zones eat into usable space. A 10,000 sq ft lot can drop to 6,500 sq ft buildable once you subtract a 25-ft front setback and 5-ft side setbacks. The tool shows gross area; for buildable area, run the numbers through the setback checker.
• Pricing fence by area instead of perimeter. Fencing is a linear cost. A 20,000 sq ft lot with a 600-ft perimeter costs more to fence than a 20,000 sq ft lot that happens to be 400 × 50 ft (perimeter 900 ft)—wait, the narrow lot actually costs 50 % more. Shape matters as much as size.
• Forgetting gates in the fence estimate. One 12-ft gate on a 600-ft perimeter is only a 2 % reduction. But if you’re quoting a farm with four 16-ft equipment gates, that’s 64 ft—over 10 % off the total. Skipping gate deductions inflates material orders and wastes money.

How many acres is a 50 × 100 ft lot? 5,000 sq ft ÷ 43,560 = 0.115 acres. That’s a standard suburban building lot in many US counties.

Does a wider lot cost more to fence than a deep one? Not necessarily. A 100 × 100 ft square (perimeter 400 ft) uses less fence than a 50 × 200 ft rectangle (perimeter 500 ft)—even though both are 10,000 sq ft. Squares minimize perimeter for a given area.

Can I use this for metric dimensions? Yes. Switch the input unit to meters and the results flip to m², hectares, and metric perimeter automatically. The acre/sq ft equivalents still show alongside.

Is this accurate enough for a contractor quote? For a ballpark material estimate, yes. For a binding contract, your contractor will want a site survey with exact grade and corner stakes.