Farm Area Calculator
Calculate your land area from length and width, or convert a value instantly between hectare, acre, square metre, square feet, guntha, bigha and katha.
Land Area Unit Reference Table
Standard conversion factors this calculator uses, relative to one square metre.
| Unit | Equivalent in Square Metres | Equivalent in Acres |
|---|---|---|
| 1 Hectare | 10,000 m² | 2.471 |
| 1 Acre | 4,046.86 m² | 1.000 |
| 1 Are | 100 m² | 0.0247 |
| 1 Guntha | 101.17 m² | 0.025 |
| 1 Square Yard | 0.836 m² | 0.000207 |
| 1 Bigha (approx.)* | ≈2,529 m² | ≈0.625 |
| 1 Katha (approx.)* | ≈126 m² | ≈0.031 |
*Bigha and Katha are traditional regional units with significant state-to-state variation — treat these as approximate reference values only.
How This Farm Area Calculator Works
Whether you know your plot's dimensions or a value in another unit, here's how the conversion happens.
Why Farm Area Conversion Is So Confusing
Land area measurement in India is a genuine patchwork. The metric system gives us hectares and square metres, British-era surveying left behind acres, square feet and square yards, and traditional regional units like bigha, katha, guntha, biswa and kanal continue to be used in land records, sale deeds and everyday conversation across different states — often with completely different sizes for the same unit name depending on which state or even district you're in. A bigha in Uttar Pradesh is not the same size as a bigha in West Bengal or Rajasthan, and a katha varies just as much. This farm area calculator handles the well-defined international units precisely, and provides a commonly cited reference conversion for bigha and katha with a clear caveat to verify locally.
Standard Land Area Units Explained
Hectare
The metric unit of area, defined as exactly 10,000 square metres, or a square measuring 100m × 100m. It's the standard unit used in most official agricultural statistics and international comparisons.
Acre
A unit from the British imperial system, equal to approximately 4,046.86 square metres or 43,560 square feet. Despite India's official shift to the metric system, acre remains extremely common in land records, real estate listings, and everyday rural conversation.
Guntha
A unit widely used in Maharashtra, Karnataka and parts of southern India, where 40 gunthas make one acre. One guntha equals roughly 101.17 square metres, or about 1,089 square feet.
Bigha
One of the most regionally inconsistent land units in India. In parts of Uttar Pradesh and Bihar, a "pucca" bigha is often cited at roughly 0.625 acre (about 2,529 square metres), while in West Bengal a bigha is considerably smaller, at around 0.33 acre. Rajasthan, Punjab, Haryana, Gujarat and other states each have their own historically established bigha sizes, sometimes varying even within the same state by district.
Katha
Typically a smaller subdivision of a bigha, commonly cited as roughly 1/20th of a bigha in regions where both units are used, though — like bigha — its exact size varies by state and even by local custom.
How to Calculate Area from Field Dimensions
For a roughly rectangular plot, area calculation is straightforward multiplication:
Area = Length × Width
Keep both measurements in the same unit before multiplying — this calculator lets you choose metres or feet, then automatically converts the resulting area into all the other units side by side. For an irregularly shaped field, the most accurate approach is to mentally (or physically) divide the plot into a few rectangular or triangular sections, calculate each section's area separately using this same method, and then add all the section areas together for a reasonably accurate total.
How to Use the Unit Converter
- Switch to the "Convert a Value" tab.
- Enter the value you already have — for example, "5" if you know your land is 5 acres.
- Select the unit that value is currently in from the dropdown.
- Tap "Convert" to instantly see the equivalent value in all nine supported units at once.
Common Land Area Conversions
| From | To | Multiply By |
|---|---|---|
| Acres | Hectares | × 0.4047 |
| Hectares | Acres | × 2.471 |
| Acres | Square Feet | × 43,560 |
| Square Metres | Square Feet | × 10.764 |
| Acres | Gunthas | × 40 |
| Gunthas | Acres | ÷ 40 |
| Acres | Bigha (approx.) | × 1.6 |
Why Accurate Land Area Matters in Farming
Field area feeds directly into nearly every other calculation a farmer makes — seed rate, fertilizer dose, irrigation water requirement, expected yield, and even lease or rental agreements are all expressed per unit area. A small error in your assumed land area compounds across every one of these downstream calculations, which is why converting confidently between whatever unit your land records use and the unit your other calculations need is genuinely useful, not just a curiosity.
Tips for Measuring Your Own Field
- Use a measuring wheel or long tape for accuracy. Pacing out distances by foot introduces significant error over larger areas.
- Measure from fixed boundary markers such as survey stones, fence lines, or established field edges rather than estimated points.
- Split irregular fields into simple shapes. Rectangles and triangles are easy to measure and calculate; irregular curves are not.
- Cross-check with land records. If you have a sale deed or land record showing area in bigha or another regional unit, use this calculator to sanity-check it against your own dimension-based measurement.
Final Thoughts
Whether you're planning a new field, cross-checking an old land record, or just need to convert a number for a conversation with a neighbouring farmer using a different unit, having instant, side-by-side conversions removes a small but recurring source of confusion. Bookmark this page and return to it any time a new unit comes up in your land dealings.
Frequently Asked Questions
One acre equals approximately 4,046.86 square metres, or about 43,560 square feet.
One hectare equals approximately 2.471 acres, since one hectare is defined as exactly 10,000 square metres.
Bigha size varies significantly by state in India, so there is no single universal conversion. This calculator uses a commonly cited reference value of about 0.625 acre (roughly 2,529 square metres), similar to conventions used in parts of Uttar Pradesh and Bihar, but you should confirm the exact local bigha size for your specific region before relying on it for legal or transactional purposes.
Forty gunthas make one acre, with each guntha equal to approximately 101.17 square metres or about 1,089 square feet.
Multiply the length by the width, keeping both measurements in the same unit, to get the area in square metres or square feet. This calculator then converts that area automatically into hectares, acres, gunthas, bigha and katha.
This calculator is intended for quick reference and planning purposes. For legal documents, land registration, or property transactions, always rely on an official land survey and your local land revenue records rather than an online estimate.
Both are traditional Indian land units that vary by region, but a katha is generally a smaller subdivision of a bigha — commonly around 1/20th of a bigha in areas where both units are used together, though exact sizes differ from state to state.
The length-times-width method works best for roughly rectangular plots. For irregular field shapes, it's more accurate to divide the field into several rectangular or triangular sections, calculate each separately, and add the results together.