Area Unit Converter

Convert between units of area.

Supported Units

• Square Kilometer (km²): The square kilometer is a unit of area equal to a square with sides of one kilometer, or 1,000,000 square meters. It is the standard unit for expressing the area of countries, states, cities, and large geographical features. For example, France covers approximately 640,000 km² and Tokyo spans about 2,194 km². In geography, environmental science, and urban planning, square kilometers are used for land-use analysis, forest coverage, and natural reserve boundaries.
• Hectare (ha): The hectare is a unit of area equal to 10,000 square meters, or a square 100 meters on each side. It is the most common unit for reporting agricultural land area worldwide. One hectare is roughly the size of 1.4 soccer fields or 2.47 acres. National parks, vineyards, and urban green spaces are often described in hectares. Although not an official SI unit, the hectare is accepted for use with the SI and is recognized by the International Bureau of Weights and Measures.
• Are (a): The are is a unit of area equal to 100 square meters, or a square 10 meters on each side. It was introduced as part of the metric system during the French Revolution. While less commonly used today than the hectare (which equals 100 ares), the are still appears in land registration documents and real estate descriptions in some countries. In Japan and parts of Europe, small plots of land may be described in ares. The prefix "hect-" in hectare literally means one hundred ares.
• Square Meter (m²): The square meter is the SI derived unit of area, representing a square with sides of one meter. It is the universal standard for measuring floor area in buildings, apartments, and commercial spaces. Real estate listings worldwide specify property sizes in square meters. In construction and architecture, building codes define requirements in terms of square meters. One square meter is approximately the area covered by a standard interior door.
• Square Centimeter (cm²): The square centimeter is a unit of area equal to a square with sides of one centimeter, or one ten-thousandth of a square meter. It is used for measuring small surfaces such as postage stamps, photographs, and adhesive bandages. In medicine, the area of skin lesions and wound surfaces is documented in square centimeters. In engineering, cross-sectional areas of wires, bolts, and structural members are often expressed in cm².
• Square Millimeter (mm²): The square millimeter is a unit of area equal to a square with sides of one millimeter, or one-millionth of a square meter. It is most commonly used in electrical engineering to specify the cross-sectional area of wire conductors (for example, "a 2.5 mm² cable"). Precision-machined parts, O-ring cross-sections, and microelectronic chip features are also measured in square millimeters. In printing, the fine details of typefaces may be analyzed at this scale.
• Acre (ac): The acre is a unit of land area in the imperial and US customary systems, defined as exactly 4,046.8564224 square meters. Its origin is medieval English, where it represented the amount of land a yoke of oxen could plow in one day. In the United States, real estate, farmland, and ranches are commonly measured in acres. One acre is approximately 0.76 of an American football field (excluding end zones). There are 640 acres in a square mile.
• Square Foot (sq ft): The square foot is a unit of area in the imperial and US customary systems, equal to a square with sides of one foot, or exactly 0.09290304 square meters. In the United States, it is the standard unit for expressing indoor floor area in real estate listings, with homes described as having, for example, "2,000 square feet." Flooring materials, carpet, and tiles are priced and sold per square foot. Commercial lease agreements also specify office and retail space in square feet.
• Square Mile (sq mi): The square mile is a unit of area in the imperial and US customary systems, equal to a square with sides of one mile, or exactly 640 acres. In the United States and United Kingdom, it is used for the areas of counties, states, cities, and other large regions. Manhattan Island in New York City covers about 23 square miles, and the City of London is just 1.12 square miles. Population density figures in English-speaking countries are typically given as persons per square mile.
• Tsubo (tsubo): The tsubo is a traditional Japanese unit of area equal to exactly 400/121 square meters (approximately 3.306 m²). It originates from the ken-based measurement system, where one tsubo equals one square ken (about 1.818 m × 1.818 m), or the area of two standard tatami mats. In Japanese real estate, land prices are often quoted per tsubo, and property sizes are commonly described in tsubo alongside square meters. Despite Japan's adoption of the metric system, the tsubo remains deeply embedded in the culture of land and housing transactions.
• Jo (jo): The jo is a Japanese unit of area based on the size of one tatami mat, standardized at 1.62 square meters for real estate purposes by the Japan Fair Trade Council. However, actual tatami dimensions vary by region: the Kyoto-style kyoma is about 1.82 m², the Tokyo-style edoma is about 1.55 m², and the Nagoya-style chukyo-ma is about 1.66 m². In Japanese housing, room sizes are almost always described in jo (for example, "a 6-jo room" or "an 8-jo living room"). This unit provides an intuitive sense of room size that is deeply rooted in Japanese residential culture.

How to Use

1. Select the unit you want to convert from in the "From" dropdown.

2. Select the unit you want to convert to in the "To" dropdown.

3. Enter a value and the result will be displayed in real time.

4. Use the swap button to reverse the conversion direction.