Area and Land Converter - Perches, Roods, Acres, Hectares, Square Feet and Square Metres
Convert land and floor area between perches, roods, acres, hectares, square feet, square metres and more.
Maintained by Hirantha Sandaruwan Lakshan. Updated 13 October 2026.
About this tool
One perch is 272.25 square feet, which is exactly 25.29285264 m², and 160 perches make an acre of 4,046.8564224 m². A helper turns an extent written as acres, roods and perches (A-R-P) into square feet and square metres, and an area back into A-R-P.
How it works
Every area is held as an exact fraction of a square metre. A square unit uses the square of its length factor, which is why 1 square foot is exactly 0.3048 x 0.3048 = 0.09290304 m² and 1 square inch is exactly 6.4516 cm². Conversions use whole numbers rather than floating point, so a conversion followed by its reverse returns the number you typed. The answer is rounded only when it is shown: Auto shows an exact result in full when it fits in 14 digits and otherwise rounds to 10 significant digits.
The perch is the square rod: a square 16.5 feet on each side, so 16.5 x 16.5 = 272.25 square feet. 40 perches make a rood and 4 roods make an acre, so an acre is 160 perches or 43,560 square feet. NIST Handbook 44 prints the square perch as 272.25 sq ft, which is 25.29285264 m², and the acre as 160 square rods. The UK Weights and Measures Act 1985 gives the acre as 4,840 square yards and the rood as 1,210 square yards. Reference works describe the division of an acre into 160 perches or 4 roods as the common one in Sri Lanka. We could not open a Sri Lankan government page that states those ratios, so that part rests on secondary sources (listed below), while the square rod, the acre and their sizes come from NIST.
Which acre? This page uses the international acre, 4,046.8564224 m², which follows from the international foot of exactly 0.3048 m. The US survey acre (about 4,046.873 m²) is based on the retired US survey foot and is larger by about 0.0004 percent. NIST asks people to stop using the survey foot from 1 January 2023, so this page does not use it.
In Sri Lanka, land is commonly described as acres, roods and perches, often written A-R-P, for example 0A-1R-20P. The Department of Census and Statistics records land extent in those three units in its national surveys. The helper adds the three boxes up, shows the total in perches, square feet, square metres, hectares and acres, and also works the other way round with the perches rounded to two decimal places. The extent on your deed or survey plan is the figure to rely on, so use this page for comparing and planning and ask a licensed surveyor for anything official.
Worked examples
10 perches in square feet and square metres
10 x 272.25 = 2,722.5 square feet. In square metres that is 10 x 25.29285264 = 252.9285264 m².
A 0A-1R-20P plot
1 rood is 40 perches, so 0A-1R-20P is 40 + 20 = 60 perches. 60 x 272.25 = 16,335 square feet, or 60 x 25.29285264 = 1,517.5711584 m².
Acres to hectares
1 acre is 0.40468564224 hectares exactly, so 5 acres is 2.0234282112 hectares. The other way, 1 hectare is 2.471053815 acres, rounded to 10 significant digits.
Square feet to perches
Divide square feet by 272.25. A 1,800 sq ft plot is 1,800 divided by 272.25 = 6.611570248 perches, rounded to 10 significant digits.
Perches in square feet, square metres, acres and hectares
| Perches | Square feet | Square metres | Acres | Hectares |
|---|---|---|---|---|
| 1 perch | 272.25 | 25.29285264 | 0.00625 | 0.002529285264 |
| 5 perches | 1,361.25 | 126.4642632 | 0.03125 | 0.01264642632 |
| 10 perches | 2,722.5 | 252.9285264 | 0.0625 | 0.02529285264 |
| 15 perches | 4,083.75 | 379.3927896 | 0.09375 | 0.03793927896 |
| 20 perches | 5,445 | 505.8570528 | 0.125 | 0.05058570528 |
| 25 perches | 6,806.25 | 632.321316 | 0.15625 | 0.0632321316 |
| 40 perches (1 rood) | 10,890 | 1,011.7141056 | 0.25 | 0.10117141056 |
| 80 perches (2 roods) | 21,780 | 2,023.4282112 | 0.5 | 0.20234282112 |
| 120 perches (3 roods) | 32,670 | 3,035.1423168 | 0.75 | 0.30351423168 |
| 160 perches (1 acre) | 43,560 | 4,046.8564224 | 1 | 0.40468564224 |
Frequently asked questions
How many square feet are in a perch?
272.25. A perch is a square rod, 16.5 feet by 16.5 feet. So 10 perches is 2,722.5 sq ft and 20 perches is 5,445 sq ft.
How many perches are in an acre?
160. An acre is 4 roods, a rood is 40 perches, and an acre is 43,560 square feet, which is 160 x 272.25.
How many square metres is a perch?
Exactly 25.29285264 m², which is usually rounded to 25.29. Some people use 25 m² as a rough figure, but that is about 1.2 percent too small, which matters when you buy land by the perch.
How do I convert square feet to perches?
Divide the square feet by 272.25. For example 2,000 sq ft is 2,000 divided by 272.25 = 7.346189164 perches. To go from perches to square feet, multiply by 272.25.
How many perches are in a hectare?
395.3686103 to 10 significant digits. A hectare is 10,000 m², and a perch is 25.29285264 m². One hectare is also 2.471053815 acres.
What is a rood?
A rood is a quarter of an acre, which is 40 perches or 1,210 square yards (UK Weights and Measures Act 1985). It is exactly 1,011.7141056 m². In A-R-P notation the middle number is roods, so 1A-2R-10P is 1 acre, 2 roods and 10 perches.
Is one acre 4,047 square metres?
To the nearest metre, yes. The exact international acre is 4,046.8564224 m². The older US survey acre is about 4,046.873 m². This page uses the international acre.
Does this give the legal extent of my land?
No. It converts numbers. For anything legal, rely on the extent on your deed or survey plan, measured by a licensed surveyor. Rounding on a plan can make a converted figure differ slightly from the printed one.
Sources & references
- NIST Handbook 44 (2026 edition), Appendix C, General Tables of Units of Measurement (exact inch, foot, yard, mile, rod, chain, furlong, square perch, acre, cup, tablespoon, teaspoon, US gallon, pound, carat, troy ounce, nautical mile), checked 2026-10-13
- Weights and Measures Act 1985, Schedule 1 (yard, mile, acre, rood, stone, pound, imperial gallon and fluid ounce definitions, as revised and current on 5 October 2026; the page flags that Schedule 1 is due to be omitted by the Product Regulation and Metrology Act 2025 from a day to be appointed, so the page may change), legislation.gov.uk, checked 2026-10-13
- NIST Special Publication 811 (2008), Appendix B.8, factors for units listed alphabetically (exact foot, inch, yard, mile, nautical mile, carat, grain, hectare, imperial gallon and the temperature formulas), checked 2026-10-13
- NIST, the U.S. survey foot (retired from 1 January 2023; 1 foot = 0.3048 m exactly), checked 2026-10-13
- Wikipedia, Acre (secondary source: says the division of an acre into 160 perches or 4 roods is common in Sri Lanka and that a perch equals a square rod), checked 2026-10-13
- Department of Census and Statistics, Sri Lanka, survey data dictionary (land extent recorded as Acres, Roods and Perches; it does not state the ratios), checked 2026-10-13
- The S Blog, The Case for Metric Land Measurements in Sri Lanka (a personal blog, not an official source: it states 272.25 square feet and 25.29 m2 to the perch, 40 perches to the rood and 4 roods to the acre), checked 2026-10-13
Updated Oct 13, 2026