Area Converter
Convert area across metric square units, international square inches, feet, yards and miles, plus ares, hectares, square rods, square chains and acres. The calculator keeps every defined factor exact and rounds only the displayed answer.
- 15 exact area units
- BigInt rational arithmetic
- Decimal or significant-figure rounding
- Full equivalent-area table
Convert Area Units
Enter one nonnegative area, select the source and target units, then choose how the final decimal should be reported. The tool converts through exact square metres without shortening a factor.
100 m² converted with exact international-foot factors.
Calculation Steps
- Use 1 m² as the exact source value in square metres.
- Use 1 ft² = 0.09290304 m² exactly.
- Calculate 100 × 1 ÷ 0.09290304 = 156250000/145161 ft² exactly.
- Round the final value once to six decimal places: 1076.391042 ft².
The unit factors are exact. The displayed decimal is rounded; it does not add precision to the original area measurement.
All Area Equivalents
Compact terminating values are shown exactly. Other comparison values are rounded to 12 significant figures and carry an approximation label.
| Unit | Equivalent area | Display status |
|---|
How to Use This Area Converter
- Enter the area. Type a nonnegative decimal or scientific-notation value without commas or a unit symbol.
- Select the source unit. Choose the square unit attached to the entered value.
- Select the target unit. Choose the unit in which you want the answer reported.
- Set the display precision. Choose decimal places or significant figures, enter the count, and select a tie rule.
- Press Convert Area. Review the rounded answer, exact fraction, square-metre base, calculation steps and complete equivalents table.
- Copy, swap or reset. Copy the active result, exchange the two unit selections without reusing a rounded answer, or restore the default example.
Zero is valid because a measured or calculated area may be zero. A negative nonzero value is rejected because ordinary physical area is a magnitude. If a formula produces a negative result, check the formula, input order or geometry before converting its unit.
The Swap Units button changes only the selected unit labels. It keeps the original typed number and recalculates from that exact input. It does not place the rounded output into the entry field, which prevents repeated conversions from accumulating rounding error.
Area Conversion Formula
Every supported unit has an exact factor expressed in square metres. The converter first changes the entered area into square metres, then divides by the target unit's square-metre factor.
For example, one international square foot equals exactly 0.09290304 square metre. To convert 100 m² into square feet, divide 100 by 0.09290304. The exact result is 156250000/145161 ft², approximately 1076.39104167 ft².
Why a length factor must be squared
Area measures a two-dimensional surface. One international foot equals exactly 0.3048 metre, but one square foot is a square with both sides one foot long. Its metric area is therefore 0.3048 m × 0.3048 m = 0.09290304 m². Multiplying a square-foot value by 0.3048 would apply a linear factor and produce the wrong dimension.
The same rule applies to square inches, square yards and square miles. A volume conversion would cube a linear factor instead, which is why area and volume units must not share one unsquared conversion multiplier.
Worked Area Conversion Examples
Example 1: Convert 2,500 ft² to m²
Multiply 2,500 by exactly 0.09290304. The result is exactly 232.2576 m². The conversion factor is exact, but a real property or floor measurement still has the accuracy of the original survey, plan or measuring method.
Example 2: Convert 1 acre to hectares
One international acre is exactly 4,046.8564224 m². Divide by 10,000 m² per hectare. One acre therefore equals exactly 0.40468564224 ha. A rounded two-decimal report is 0.40 ha, while six decimal places give 0.404686 ha.
Example 3: Convert 1 hectare to acres
Reverse the relationship by dividing 10,000 m² by the exact square-metre value of one acre. The exact result is 390625000/158080329 acre, approximately 2.47105381467 acres. Six decimal places produce 2.471054 ac.
Example 4: Convert 1 square mile to square kilometres
One international mile equals exactly 1,609.344 metres. Squaring that definition gives exactly 2,589,988.110336 m², or 2.589988110336 km². This is also exactly 640 international acres.
Example 5: Convert 144 in² to ft²
One foot contains 12 inches along each side. A square foot therefore contains 12 × 12 = 144 square inches. The result is exactly 1 ft², not 12 ft².
Common Area Conversion Table
Exact values are marked as such. Repeating decimal values are shown to 12 significant figures for comparison.
| Starting area | Converted area | Status |
|---|---|---|
| 1 m² | 10.7639104167 ft² | Rounded display |
| 1 ft² | 0.09290304 m² | Exact |
| 1 yd² | 0.83612736 m² | Exact |
| 1 in² | 6.4516 cm² | Exact |
| 1 ha | 10,000 m² | Exact |
| 1 ha | 2.47105381467 ac | Rounded display |
| 1 ac | 4,046.8564224 m² | Exact |
| 1 ac | 0.40468564224 ha | Exact |
| 1 km² | 100 ha | Exact |
| 1 mi² | 2.589988110336 km² | Exact |
| 1 ch² | 0.1 ac | Exact |
| 1 rd² | 272.25 ft² | Exact |
Metric, International and Land-Area Units
The square metre is the coherent SI unit of area. Metric prefixes apply to the metre before it is squared. One square centimetre is (0.01 m)², so it equals 0.0001 m², not 0.01 m². One square kilometre is (1,000 m)², so it equals 1,000,000 m².
- Square micrometre, millimetre, centimetre and decimetre: useful for microscopic, technical, product and drawing areas.
- Square metre: the standard SI area unit for rooms, buildings, materials and general measurement.
- Are and hectare: one are equals 100 m²; one hectare equals 100 ares or 10,000 m².
- Square kilometre: equals 1,000,000 m² or 100 hectares and suits large geographic areas.
- Square inch, foot and yard: based on the international inch, foot and yard definitions.
- Square rod and square chain: historical survey-area units retained for clearly labelled records.
- Acre and square mile: one acre equals 43,560 ft²; one square mile equals 640 acres.
This converter uses the international foot basis for every foot-derived unit. It does not silently mix international and legacy U.S. survey-foot values.
Land Records, Regional Units and the U.S. Survey Foot
A unit label is safe only when its definition is clear. Bigha, biswa, katha, dhur, kanal, marla, ground, gaj, cent, decimal and guntha or gunta can appear in South Asian land records, but their definitions or usage are not uniform across jurisdictions. A single generic dropdown value could therefore produce a confident but wrong land conversion.
These region-dependent units are intentionally omitted. If your deed or land record uses one, first identify the state, district, record system and printed conversion basis. Convert the locally defined unit into square metres, hectares or acres, then use a standard unit here. Plain gaj is a length label in some contexts; square gaj is often used for square yard, so the word alone should not be guessed as area.
The United States retired general use of the U.S. survey foot after December 31, 2022. This page uses the international foot, exactly 0.3048 metre, for square feet, square yards, square rods, square chains, acres and square miles. Historical survey datasets may retain survey-foot coordinates or areas. Keep that legacy basis explicit and use a specialist conversion rather than treating a survey acre as the plain acre in this calculator.
Exact Factors, Rounding and Measurement Precision
The factors in this calculator are exact definitions or exact relationships derived from them. Exact arithmetic prevents a shortened constant from affecting later digits. It does not make a measured plot, floor, map or material area more accurate than its source.
- Exact target value: the complete rational result before display rounding.
- Decimal places: counts positions to the right of the decimal point.
- Significant figures: counts meaningful digits from the first nonzero digit.
- Ties to even: sends an exact halfway value to the result with an even retained digit.
- Ties away from zero: increases the magnitude at an exact halfway point.
- Equivalent table: uses up to 12 significant figures so very small and large values remain visible.
The main result uses the selected precision. The equals sign appears only when that displayed value is still exact. An approximation sign appears when rounding discards a nonzero remainder. Keep guard digits through a larger calculation and round once at the final reporting step.
Choose precision from the purpose and source data. A cadastral survey, construction quantity, classroom exercise and rough property listing may require different reporting. More decimal places change the display, not the original measurement uncertainty or boundary authority.
Common Area Conversion Mistakes
- Using a linear factor. Square the length relationship before applying it to area.
- Moving a metric decimal once instead of twice. One cm² equals 0.0001 m², not 0.01 m².
- Assuming 1 acre equals 4,000 m² exactly. The international acre is exactly 4,046.8564224 m².
- Confusing hectare and acre. One hectare is larger and equals about 2.47105381467 acres.
- Mixing international and survey-foot factors. Legacy survey data needs an explicitly labelled basis.
- Guessing a regional land unit. Check the jurisdiction-specific definition before conversion.
- Rounding a factor early. Keep the defined factor exact and round the final result once.
- Using conversion to find area. A converter changes units; the separate Area Calculator finds area from shape dimensions.
- Dropping the squared symbol. Metres and square metres describe different physical quantities.
Related Calculators
Browse the Unit Conversion & Measurement Calculators directory or continue with these verified tools.
Frequently Asked Questions
How do I convert one area unit to another?
Multiply the entered area by the source unit's exact square-metre factor, then divide by the target unit's exact square-metre factor. Round only the final displayed value.
Why must I square a length conversion factor for area?
Area has two length dimensions. Both sides of a square change unit, so the linear factor applies twice. For example, 1 ft² equals 0.3048² m², or exactly 0.09290304 m².
How many square feet are in 1 square metre?
One square metre equals exactly 1562500/145161 square feet, approximately 10.7639104167 ft². The decimal does not terminate, so a finite decimal is rounded.
How many square metres are in 1 square foot?
One international square foot equals exactly 0.09290304 m². This comes from squaring the exact international-foot definition of 0.3048 metre.
How many square metres are in 1 acre?
One international acre equals exactly 4,046.8564224 m². It also equals exactly 43,560 square feet or 4,840 square yards.
How many acres are in 1 hectare?
One hectare equals exactly 10,000 m² and approximately 2.47105381467 international acres. Rounded to six decimal places, it is 2.471054 acres.
What is the difference between an acre and a hectare?
An acre is a foot-derived land unit equal to exactly 4,046.8564224 m². A hectare is a metric land unit equal to exactly 10,000 m², so a hectare is larger.
Does this converter use the U.S. survey foot?
No. Plain square feet, acres and related units use the current international foot of exactly 0.3048 metre. Legacy survey-foot data needs an explicitly labelled specialist conversion.
Why are bigha, marla, kanal and similar units not included?
Their definitions vary by jurisdiction or record system. A single generic factor could be wrong. Check the definition printed or prescribed for your local land record before converting it to a standard unit.
Can an area be negative?
Ordinary physical area is nonnegative, so the calculator rejects a negative nonzero entry. Zero is accepted. A negative formula result usually indicates an input-order, sign or geometry issue.
Calculation Method and Review Basis
Area factors were checked against the 2026 NIST Handbook 44 area tables and NIST's revised foot-based conversion factors. SI units, the are and the hectare were checked against the BIPM SI Brochure. Regional land-unit variation was reviewed against the Government of India land-region and unit coding tables.
Measurement and land disclaimer: This converter changes a typed area between defined units. It does not establish a legal boundary, title, cadastral value, survey accuracy, construction quantity, valuation or measurement uncertainty. Confirm the governing unit definition, source measurement, precision and professional requirements for property, engineering, trade, tax, safety or regulated work.