Quick answer
Land area for a rectangle is A × B, a triangle ½·A·B and a circle π·A², with 1 acre = 43,560 ft² = 4,046.86 m². A 200 × 150 ft lot has 30,000 ft², 0.6887 acres, 2,787.09 m² and 0.2787 hectares.
Choose a shape and enter its dimensions and length unit. The calculator returns the area in square feet, acres, square metres and hectares.
Related tools: Price per Square Foot Calculator: Price divided by floor area. Property Appreciation Calculator: Projected property value at an assumed yearly appreciation rate. Property Tax Estimate Calculator: Annual property tax from an assessed value and the rate you enter.
How to use the Land Area Calculator
- Choose shape: Rectangle (A × B), Triangle (base A, height B) and Circle (radius A).
- Choose length unit: Feet, Yards and Meters.
- Enter dimension A (above 0).
- Optionally, enter dimension B (above 0).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Shape | Choose one: Rectangle (A × B); Triangle (base A, height B); Circle (radius A) | Starts at Rectangle (A × B) |
| Length unit | Choose one: Feet; Yards; Meters | Starts at Feet |
| Dimension A | A number | > 0 |
| Dimension B (optional) | A number | > 0 |
Formula and method
Formula
rectangle A·B; triangle ½·A·B; circle π·A²; 1 acre = 43,560 ft² = 4,046.8564224 m²
IEEE-754 double precision; money shown to cents, rates to 4 decimals. Results are estimates, not financial advice.
Feet and yards convert to meters exactly (0.3048 m and 0.9144 m).
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Shape = Rectangle (A × B); Length unit = Feet; Dimension A = 200; Dimension B = 150.
| Result | Value |
|---|---|
| Area (sq ft) | 30,000 |
| Acres | 0.6887 |
| Square meters | 2,787.0912 |
| Hectares | 0.278709 |
Example 2
Inputs: Shape = Triangle (base A, height B); Length unit = Meters; Dimension A = 40; Dimension B = 25.
| Result | Value |
|---|---|
| Area (sq m) | 500 |
| Acres | 0.1236 |
| Square meters | 500 |
| Hectares | 0.05 |
Example 3
Inputs: Shape = Circle (radius A); Length unit = Yards; Dimension A = 30.
| Result | Value |
|---|---|
| Area (sq yd) | 2,827.4334 |
| Acres | 0.5842 |
| Square meters | 2,364.0944 |
| Hectares | 0.236409 |
The first line is the headline result (area (sq ft)). Below it the land Area Calculator lists acres, square meters and hectares, which describe the same case from other angles. IEEE-754 double precision; money shown to cents, rates to 4 decimals. Results are estimates, not financial advice.
Conversions
30,000 ÷ 43,560 = 0.6887 acres. 1 hectare = 10,000 m² = 2.471 acres. A square acre is about 208.7 ft per side.
Irregular lots
Split an irregular lot into rectangles and triangles, calculate each and add them. Deeds and surveys give the legal area; this is a measurement aid. Rectangles and triangles need dimension B.
How the result changes with dimension A
Holding every other input at the first worked example, this table changes only dimension A. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Dimension A | Area (sq ft) | Acres | Square meters |
|---|---|---|---|
| 100 | 15,000 | 0.3444 | 1,393.5456 |
| 200 | 30,000 | 0.6887 | 2,787.0912 |
| 400 | 60,000 | 1.3774 | 5,574.1824 |
| 800 | 120,000 | 2.7548 | 11,148.3648 |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Dimension B: left empty shows "Enter dimension B." beside that field and no result.
- Dimension A: entering "0" shows "Dimension A must be greater than 0." beside that field and no result.
Choosing between the Land Area Calculator and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Price per Square Foot Calculator](/real-estate/price-per-sqft/) | price and area | Price per sq ft |
| [Property Appreciation Calculator](/real-estate/property-appreciation-calculator/) | current value, annual appreciation and years | Projected value |
| [Property Tax Estimate Calculator](/real-estate/property-tax-estimate-calculator/) | assessed value and tax rate | Annual property tax |
| [Area Calculator](/math/area-calculator/) | shape and a | Area |
| [Area Converter](/converters/area-converter/) | value, from and to | Cent (1/100 acre) → Square metre (m²) |
Background: rental property metrics
Rental property metrics answer different questions. The cap rate is net operating income divided by the purchase price and ignores financing; cash flow is income minus operating expenses minus debt service; cash-on-cash return divides annual cash flow by the cash you actually invested. Rules of thumb such as the 1% rule (monthly rent at least 1% of the price) are quick screens, not decisions.
Check the assumptions behind any result: vacancy, management fees, repairs and taxes. Published benchmark ranges for a good cap rate or return vary between sources.
Assumptions and limitations
- Rectangles and triangles need dimension B
Estimates only. Taxes, fees and lender or authority rules vary by place and date, so confirm figures with the relevant authority or professional.
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for dimension B and dimension A to confirm this.
Frequently asked questions
How many acres is 1 hectare?
1 hectare is 10,000 m², which is about 2.471 acres.
How big is half an acre?
Half an acre is 21,780 ft² (43,560 ÷ 2), about 2,023 m².
Is a survey needed?
For legal boundaries, yes.
What does the Land Area Calculator calculate?
Area of a rectangular, triangular or circular lot in acres, hectares and square units. It returns Area (sq ft), Acres, Square meters and Hectares.
What formula does the Land Area Calculator use?
rectangle A·B; triangle ½·A·B; circle π·A²; 1 acre = 43,560 ft² = 4,046.8564224 m². Feet and yards convert to meters exactly (0.3048 m and 0.9144 m).
What do I need to enter in the land Area Calculator?
You enter Shape, Length unit and Dimension A. Optional: Dimension B.
How is the result rounded or limited?
IEEE-754 double precision; money shown to cents, rates to 4 decimals. Results are estimates, not financial advice. Rectangles and triangles need dimension B.
What does the “Shape” option change?
It sets how the land Area is worked out. The choices are Rectangle (A × B), Triangle (base A, height B) and Circle (radius A).
What is an example of a land Area result?
With shape Rectangle (A × B), length unit Feet, dimension A 200 and dimension B 150, the area (sq ft) is 30,000.
Can I rely on this calculator for a decision?
Estimates only. Taxes, fees and lender or authority rules vary by place and date, so confirm figures with the relevant authority or professional. For this calculator in particular: Rectangles and triangles need dimension B.
Related calculators
- Price per Square Foot Calculator — Price divided by floor area.
- Property Appreciation Calculator — Projected property value at an assumed yearly appreciation rate.
- Property Tax Estimate Calculator — Annual property tax from an assessed value and the rate you enter.
- Area Calculator — Area of common two-dimensional shapes.
- Area Converter — Convert square metres, feet, acres, hectares and more.
- Home Equity Calculator — Equity, loan-to-value and borrowing room against a lender limit.
Sources
- Standard time-value-of-money relations (e.g. Brealey, Myers & Allen, Principles of Corporate Finance)
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.