This acreage calculator converts land dimensions into acres, square feet and square metres for rectangular, triangular and circular lots — plus what common acre fractions actually look like on the ground.
| Area | – |
| Acres | – |
| Square metres / hectares | – |
| Ground truth | – |
One Acre = 43,560 sq ft — a Furlong’s Ghost in Your Lot Lines
The acre descends from a day’s plowing: one chain (66 ft) by one furlong (660 ft). Unit-shuffling of a different kind lives in our Area Converter. Part of our Conversion Calculators collection.
Worked Example (Verified)
- 100 × 250 ft lot (defaults): 25,000 sq ft = 0.5739 acres ≈ 2,322 m² — the “half-acre” listing that rounds generously in the seller’s favor
- The square-acre anchor: 208.71 ft × 208.71 ft = exactly 1 acre (the football-field comparison most people actually carry: a field with end zones is 1.32 acres)
- Subdivision reality: a typical modern suburban lot of 60 × 110 ft = 6,600 sq ft = 0.1515 acre — “quarter-acre” marketing survives mostly in HOA names
- Irregular parcels: break them into rectangles + triangles and add — surveyors’ decomposition, and this tool’s three shapes cover it
Land-Measure Discipline
- Deeds speak in chains, rods (16.5 ft) and perches in older surveys — 1 acre = 160 square rods = 10 square chains.
- Sloped land measures smaller on the map than on the ground: acreage is the horizontal projection, fences follow the hill.
- Buildable ≠ total: easements, setbacks, wetlands and rights-of-way carve the usable lot out of the paper lot.
- GIS acreage from county sites is planning-grade; a boundary survey is the legal instrument — closing and fencing decisions deserve the survey.
Related Tools
- Area Converter — acres, hectares & more units
- Coordinate Converter — lot corners in DMS/decimal
- Conversion Calculators — the full collection
Frequently Asked Questions
How do I calculate acres from feet?
Multiply length × width for square feet, then divide by 43,560. A 100 × 250 ft lot: 25,000 ÷ 43,560 = 0.5739 acres. This calculator also handles triangular and circular lots and converts to m² and hectares.
How big is an acre visually?
About 91% of an American football field’s playing surface between the goal lines (1.10 acres); including end zones the full field is 1.32 acres, making an acre ≈ 76% of it. Alternatively: a square 208.7 ft on a side. Most people underestimate it standing on one — paced off, it’s a serious walk.
How many square feet are in a quarter acre?
10,890 sq ft — e.g., a lot about 99 × 110 ft or 66 × 165 ft. Half acre = 21,780 sq ft; the defaults’ 25,000 sq ft lot is a 0.574-acre parcel wearing a “generous half” description honestly.
What is a hectare in acres?
1 hectare = 10,000 m² = 2.471 acres; 1 acre = 0.4047 hectares. Metric-country land listings in hectares convert directly in this tool’s third row.
How do I measure an irregular lot?
Decompose it: rectangles where it’s rectangular, triangles for the angled corners, and add the pieces (each shape is a mode here). For high-stakes precision — purchases, disputes, tax appeals — a licensed survey supersedes any decomposition.
Is this acreage calculator free?
Yes — free, instant, no sign-up.