Area Converter
Convert between metric and imperial units of area — square metres, hectares, acres, square feet and square miles — using exactly defined conversion factors.
Area Converter
Results recalculate instantly on every keystroke. Nothing you type is transmitted.
What this result does not account for
- Results are a model, not a quotation — an institution's own figures govern.
- Every input is an assumption; change one and the answer changes with it.
- Rounding is applied only at the display layer, so totals may differ by a cent from a statement that rounds each line.
In short: Area conversion routes every value through the square metre, the SI derived unit. Because the inch is defined as exactly 0.0254 m, the square foot is exactly 0.09290304 m² and the acre exactly 4046.8564224 m², so imperial area conversions are exact rather than approximate.
Formula
Each factor is the number of square metres in one of that unit. Dividing by the target factor completes the conversion in a single step, avoiding intermediate rounding.
Worked Example
- Identify the source factor. One acre is exactly 4046.8564224 m².
- Convert to the SI unit. 1 × 4046.8564224 = 4046.8564224 m².
- Identify the target factor. One square metre is 1 m².
- Divide. 4046.8564224 ÷ 1 = 4,046.8564 m².
- Sense-check it. An acre is 43,560 ft², and 4046.8564224 ÷ 0.09290304 returns exactly that.
Metrology note. The acre is defined as 4,840 square yards, which resolves to exactly 4046.8564224 m² because the yard is exactly 0.9144 m. No rounding is involved at any stage, so the conversion is exact rather than a decimal approximation.
Strengths & Limits Of This Model
Where this engine is strong
- Runs entirely in your browser — no figure you type is transmitted or stored.
- Shows the full working, so every number can be traced and challenged.
- Free, unmetered and free of affiliate incentives.
Where it stops
- Generalised assumptions cannot capture every individual circumstance.
- Jurisdiction-specific rules and mid-year changes may not be reflected.
- A model output is not a substitute for a professional review of your position.
Practical Use Cases
Sizing land parcels across measurement systems
Property listings switch between acres, hectares and square feet depending on jurisdiction. Converting to a single unit is the only reliable way to compare parcels, and the equivalent square side helps visualise the footprint. For built area, the Area Calculator handles shapes other than rectangles.
Estimating materials for a floor or roof
Flooring, roofing and turf are all sold per unit area, frequently in different units from the plan. Convert first, then add a wastage allowance. The Tile Calculator applies the trade allowances for you.
Reading agricultural and survey data
Agronomic yields are usually quoted per hectare outside the United States and per acre inside it, a factor of roughly 2.47 apart. Converting before comparing avoids a very common order-of-magnitude error in reported yields.
Methodology & Editorial Standards
Every unit is stored as an exact multiple of the square metre. Imperial areas derive from the international inch of exactly 0.0254 m, giving a square foot of exactly 0.09290304 m² and an acre of exactly 4046.8564224 m² by way of its definition as 4,840 square yards. The hectare is exactly 10,000 m² by definition. Conversion is performed in a single multiply-divide step at full double precision, so no intermediate rounding occurs. All conversion factors are exact by definition under the International System of Units, or exact by international agreement where the unit is defined by treaty. Values are held at full IEEE-754 double precision internally and rounded only for display, so chained conversions do not accumulate drift.
Computation runs in IEEE-754 double precision at full internal precision; rounding to two decimal places occurs strictly at the display layer, so no cumulative drift enters the result. All monetary outputs use accounting presentation — grouped thousands, two decimals, negatives in parentheses — so figures can be transcribed directly into a model or working paper. Division-by-zero and out-of-domain inputs return an em-dash rather than a misleading number.
This engine was reconciled against an independent reference implementation and hand-verified for the worked example above before release. Our full five-stage review process is published on the About Us page.
Disclaimer. This calculator is provided for informational and modelling purposes only and does not constitute financial, tax, legal, medical, or engineering advice. Verify all figures with a qualified professional before acting on them.
Area Converter — 20 Expert FAQs
20 analyst-written answers to the questions practitioners actually ask — optimised for voice and answer-engine retrieval.
How many square feet are in an acre?
Exactly 43,560 square feet. The acre is defined as 4,840 square yards, and each square yard is nine square feet, so the figure is exact rather than rounded.
How many acres are in a hectare?
About 2.4710538 acres. A hectare is exactly 10,000 m² while an acre is exactly 4046.8564224 m², so the ratio is an exact fraction that produces a non-terminating decimal.
Is the conversion between square feet and square metres exact?
Yes. One square foot is exactly 0.09290304 m², because the international inch has been defined as exactly 0.0254 m since the 1959 international yard and pound agreement.
Why is area not simply the length factor doubled?
Because area scales with the square of length. One foot is 0.3048 m, so one square foot is 0.3048² = 0.09290304 m². Doubling a length quadruples the area, which is the single most common error in manual area conversion.
What is the difference between an acre and a hectare?
Both measure land, but the acre is an imperial unit of 4046.8564224 m² and the hectare is metric at exactly 10,000 m². A hectare is roughly two and a half acres, so the two are not interchangeable even approximately.
How large is a square mile?
Exactly 2,589,988.110336 m², or 640 acres. The relationship to the acre is exact by definition, which is why section-based land survey systems use both units together.
What is an 'are'?
An are is 100 m², a square ten metres on each side. It is the root unit of the hectare, which is literally a hundred ares. The are itself is rarely used today outside a few European land registries.
Why does the calculator show an equivalent square side?
Because area alone is hard to picture. Knowing that 4,047 m² is a square roughly 63.6 m on each side makes the magnitude concrete, which is useful when checking whether a figure is plausible.
Can I convert between area and length units?
No, and the calculator will not let you. Area and length are different physical dimensions. Converting square metres to metres is not a unit conversion but a geometric operation requiring a second dimension.
What is a square mil?
One millionth of a square inch, used in electronics for conductor cross-sections. A mil is one thousandth of an inch, so a square mil is exactly 0.00000064516 m².
Are US and imperial acres the same?
For all practical purposes, yes. The international acre used here is exact. The US survey acre differs by about two parts per million, a distinction that matters only in cadastral surveying, and the US survey foot was formally deprecated at the end of 2022.
How precise are the results?
Values are computed at IEEE-754 double precision, roughly sixteen significant figures, and displayed to eight. Because the factors themselves are exact, the only error is the final display rounding.
Is this area converter free to use?
Yes. It is free, requires no account, and has no usage limits. ApexConverter is funded by contextual advertising, never by selling user data.
Is my data sent to a server?
No. The engine runs as Vanilla JavaScript inside your browser under our Zero-Server Client-Side Execution model. Your figures are computed locally and are never transmitted, logged, or stored.
How accurate is this calculator?
It applies the standard closed-form formula in IEEE-754 double precision, rounding only at the display layer. The engine is reconciled against an independent reference implementation before release.
Does it work on mobile?
Yes. The interface is mobile-first with numeric keypad hints and is tested down to a 320-pixel viewport with no horizontal scrolling.
Can I use it offline?
Largely, yes. Because computation is client-side, the page continues to calculate without a network connection once it has loaded.
Which currency does it use?
Amounts display in US$ accounting format, but the underlying mathematics is currency-agnostic. The result is identical in any currency, so simply read the figures in your own.
Why does a result show an em-dash?
An em-dash indicates the calculation is not defined for the inputs given — typically a division by zero or a value outside the valid domain. We show a dash rather than a misleading number.
How do I report an error?
Email apexconverter.praxiscalc@gmail.com with the tool URL, your exact inputs, the output received and the output you expected. Verified mathematical errors are patched within 72 hours.