Area Converter

Area Factors Are Squared Length Factors

The single most common error in area conversion is reaching for the length factor. A foot is 0.3048 m, so people assume a square foot is 0.3048 square metres. It isn't — it's 0.3048² = 0.09290304 m², roughly a tenth. Every factor in this converter is a length factor squared, which is why the numbers look unfamiliar even to people comfortable with linear conversion. Get the square wrong and you're out by a factor of three or more.

The Formula

The converter holds each unit's area in square metres and pivots through that base:

Result = Value × (Factor of From-Unit) ÷ (Factor of To-Unit)
(Factors are relative to 1 square meter)

Negative input is rejected outright — area cannot be less than zero, and a negative value almost always signals a data-entry mistake upstream.

The Factor Table

Area units and their exact value in square metres
UnitCodeSquare metres per unitDerivation
Square Millimetersmm20.0000010.001²
Square Centimeterscm20.00010.01²
Square Metersm21base
Hectareshectare10000100 m × 100 m
Square Kilometerskm210000001000²
Square Inchesin20.000645160.0254²
Square Feetft20.092903040.3048²
Square Yardsyd20.836127360.9144²
Acresacre4046.85642244840 yd²
Square Milesmi22589988.1103361609.344²

Full Conversion Reference

1 unit of area converted to square metres, square feet, acres and hectares
1 of…Square MetersSquare FeetAcresHectares
Square Millimeter0.0000010.000010762.471054e-101.0e-10
Square Centimeter0.00010.001076392.471054e-081.0e-08
Square Meter110.763910420.000247110.0001
Hectare10000107639.10422.471053811
Square Kilometer100000010763910.4167247.10538147100
Square Inch0.000645160.006944441.594225e-076.4516e-08
Square Foot0.0929030410.000022960.00000929
Square Yard0.8361273690.000206610.00008361
Acre4046.85642244356010.40468564
Square Mile2589988.11033627878400640258.99881103

Two relationships in that table are exact whole numbers worth knowing: 1 square yard = 9 square feet, and 1 square mile = 640 acres. The 640 is why US land was historically surveyed in one-square-mile "sections".

Land Parcels: Acres, Hectares and Square Feet

Common parcel sizes across the three land units
AcresSquare MetersHectaresSquare Feet
0.251011.71410560.1011714110890
0.52023.42821120.2023428221780
14046.85642240.4046856443560
520234.2821122.02342821217800
1040468.5642244.04685642435600

Floor Areas

Typical listed floor areas converted from square feet to square metres
Square FeetSquare Meters
50046.45152
100092.90304
1500139.35456
2000185.80608
2500232.2576

Where This Gets Used

  • Property listings across markets — the same home advertised at 2,000 sq ft in one market is 185.80608 m² in another, and buyers comparing internationally need the exact figure.
  • Agricultural planning — seed, fertiliser and yield rates are published per hectare in most of the world and per acre in the US; the 2.47105381 factor between them decides application rates.
  • Flooring and material orders — carpet and tile priced per square yard against a room measured in square feet (divide by 9), or metric stock against imperial plans.
  • Land valuation — converting a price per acre into a price per square metre to compare against a differently quoted parcel.

How to Use This Calculator

  1. Enter the area figure into the Value field. It must be zero or positive.
  2. Select the unit that figure is in from the first dropdown.
  3. Select your target unit from the second dropdown.
  4. Choose Calculate. The breakdown lists both squared factors, making the arithmetic verifiable.

Related Calculations

Working from linear measurements? Convert them first with the Length Converter. For three-dimensional capacity rather than flat area, see the Volume Converter.