Sri Lanka Land Area Converter
Convert between the units a Sri Lankan deed, survey plan or property ad is likely to use — perches, square feet, square metres, square yards, roods, acres, hectares and cents — or parse a deed string such as 2a-1r-30p directly.
Converted area
8 units · liveAbout these figures, and how the conversion is done
Sri Lankan land has historically been measured in the old British system — perches, roods and acres — because the Land Registry's deed records predate metrication. Survey plans and government cadastral work now run in square metres and hectares instead, and everyday listings also use square feet, square yards and, in the north and east, cents. This tool converts between all eight so a figure from any one source can be checked against another.
A perch is a square 16.5 feet on each side — so 1 perch = 16.5 × 16.5 = 272.25 ft² exactly, with no rounding, since the definition starts in feet. Every other figure is derived from the same SI-exact starting point (1 ft = 0.3048 m, by international agreement), so a perch works out to 25.29285264 m² to full precision.
| Relationship | Value |
|---|---|
| 1 perch | 272.25 ft² = 25.29285264 m² |
| 1 rood | 40 perches |
| 1 acre | 4 roods = 160 perches = 43,560 ft² |
| 1 hectare | 10,000 m² ≈ 395.3686 perches |
| 1 cent | 1⁄100 acre = 1.6 perches |
Internally, every amount is first converted to square metres using exact factors, then divided back out into the other seven units — rather than converting unit-to-unit directly — so results stay consistent with each other no matter which unit you start from. The small "cross-check" line above computes the perch→square-feet figure a second way, using only the imperial definition with no metric step at all, purely to confirm the two routes agree.
Deed notation (the "a-r-p" format used on titles and survey plans) is just a way of writing a perch total split into acres, roods and leftover perches: multiply the acres by 160 and the roods by 40, add the perches, and you have the total in perches — which this tool then converts into whatever other unit you need.
Six conversions worth knowing by heart
Hectare → perch
A hectare (10,000 m²) holds 395.3686 perches, since each perch is 25.29285264 m² — so dividing 10,000 by that figure gives the ratio. For a rough mental check, 395.37 is close enough: 2 ha lands around 790.7 perches, and a half-hectare plot around 197.7 perches. In the older system that same half-hectare reads as roughly 1.24 acres.
1 ha = 395.3686 p = 2.4711 ac
Perch → square feet
Because a perch is defined as a 16.5 ft square, 16.5 × 16.5 gives 272.25 square feet with no rounding at all — it never has to touch the metric system to get there. Multiplying straight through: 10 perches is 2,722.5 ft², 15 perches is 4,083.75 ft², and 20 perches is 5,445 ft².
1 p = 272.25 ft² = 30.25 yd²
Square feet → perch
Reverse the multiplication above by dividing the floor area by 272.25. A 1,000 ft² plate works out to roughly 3.67 perches, 2,400 ft² to about 8.82 perches, and 5,000 ft² to about 18.37 perches. Worth remembering as a landmark: 2,722.5 ft² is exactly 10 perches.
1 ft² ≈ 0.003673 p
Acre → perch
An acre is defined as 4 roods, and each rood is 40 perches, so 4 × 40 gives the 160-perch figure every Sri Lankan deed and property ad is ultimately built on. Two acres is 320 perches, five acres is 800, half an acre is 80. Going backwards, any perch count divided by 160 gives acres — 160 ÷ 160 lands exactly on 1 acre, equal to 43,560 ft² or 4,046.8564 m².
1 ac = 160 p = 4 r
Perch → hectare
Divide a perch count by 395.3686 (or multiply by roughly 0.0025293) to get hectares. On that basis 100 perches comes to about 0.2529 ha, 160 perches (one acre) to about 0.4047 ha, and 1,000 perches to about 2.5293 ha. The calculator above always works from the exact 25.29285264 m² figure rather than a rounded one, so small inputs stay accurate.
1 p ≈ 0.0025293 ha
Rood → perch
A rood is a quarter of an acre — 40 perches, 10,890 ft², or about 1,011.71 m². It's the middle figure in deed notation, so a deed reading 0a-2r-0p is 80 perches and 1a-1r-0p is 200 perches. The rood figure in that notation never reaches 4, because a fourth rood simply rolls over into an extra acre.
1 r = 40 p = 10,890 ft²
Reference tables
Figures below are rounded for display; the converter above carries full precision.
Perches, 1–160
| Perches | Sq. feet | Sq. metres | Acres | Hectares |
|---|---|---|---|---|
| 1 | 272.25 | 25.29 | 0.00625 | 0.002529 |
| 5 | 1,361.25 | 126.46 | 0.03125 | 0.012646 |
| 10 | 2,722.50 | 252.93 | 0.06250 | 0.025293 |
| 15 | 4,083.75 | 379.39 | 0.09375 | 0.037939 |
| 20 | 5,445.00 | 505.86 | 0.12500 | 0.050586 |
| 25 | 6,806.25 | 632.32 | 0.15625 | 0.063232 |
| 30 | 8,167.50 | 758.79 | 0.18750 | 0.075879 |
| 40 (1 rood) | 10,890.00 | 1,011.71 | 0.25000 | 0.101171 |
| 50 | 13,612.50 | 1,264.64 | 0.31250 | 0.126464 |
| 75 | 20,418.75 | 1,896.96 | 0.46875 | 0.189696 |
| 100 | 27,225.00 | 2,529.29 | 0.62500 | 0.252929 |
| 160 (1 acre) | 43,560.00 | 4,046.86 | 1.00000 | 0.404686 |
Acres, 1–10
| Acres | Perches | Roods | Sq. feet | Hectares |
|---|---|---|---|---|
| 1 | 160 | 4 | 43,560 | 0.404686 |
| 2 | 320 | 8 | 87,120 | 0.809371 |
| 3 | 480 | 12 | 130,680 | 1.214057 |
| 5 | 800 | 20 | 217,800 | 2.023428 |
| 10 | 1,600 | 40 | 435,600 | 4.046856 |
Hectares, 0.1–10
| Hectares | Perches | Acres | Sq. metres | Sq. feet |
|---|---|---|---|---|
| 0.10 | 39.5369 | 0.2471 | 1,000 | 10,764 |
| 0.25 | 98.8422 | 0.6178 | 2,500 | 26,910 |
| 0.50 | 197.6843 | 1.2355 | 5,000 | 53,820 |
| 1 | 395.3686 | 2.4711 | 10,000 | 107,639 |
| 2 | 790.7372 | 4.9421 | 20,000 | 215,278 |
| 5 | 1,976.8431 | 12.3553 | 50,000 | 538,196 |
| 10 | 3,953.6861 | 24.7105 | 100,000 | 1,076,391 |
Worked examples
A 15-perch Colombo plot
- Start: 15 perches
- Square metres: 15 × 25.29285264 = 379.3928 m²
- Square feet, straight from the perch definition: 15 × 272.25 = 4,083.75 ft²
- Square feet, by going through metres instead: 379.3928 ÷ 0.09290304 = 4,083.75 ft² — the two agree
- Acres: 15 ÷ 160 = 0.09375
- Hectares: 379.3928 ÷ 10,000 ≈ 0.0379
- Deed notation: 0a-0r-15p
An estate quoted as 2a-1r-30p
- Parse the deed: (2 × 160) + (1 × 40) + 30 = 390 perches
- Square metres: 390 × 25.29285264 ≈ 9,864.21 m²
- Acres: 390 ÷ 160 = 2.4375 — which checks out as 2 whole acres + 1 rood (0.25) + 30⁄160 of an acre
- Hectares: 9,864.21 ÷ 10,000 ≈ 0.9864
- Square feet: 390 × 272.25 = 106,177.5
- Cents: 2.4375 × 100 = 243.75
- Re-encoding 390 perches back into a-r-p returns 2a-1r-30p with nothing lost
A 10-cent plot (North & East convention)
- Start: 10 cents
- Square metres: 10 × 40.468564224 ≈ 404.69 m²
- Perches: 10 × 1.6 = 16 (exact, since 1 cent is defined as 1.6 perches)
- Square feet: 16 × 272.25 = 4,356
- Acres: 0.1
- Deed notation: 0a-0r-16p
Not a substitute for a licensed surveyor or the Registrar of Lands — for anything that will go on a legal document, confirm figures against the actual survey plan or deed.
