Polygon Area Perimeter Calculator - Calculate Area Online

Input Method

Manual Input (GeoJSON/WKT)Draw on Map

Polygon Data (GeoJSON or WKT)

Click on the map to draw a polygon. Double-click to finish.

Area Unit

Square Meters (m²)Square Kilometers (km²)Hectares (ha)Square Miles (mi²)AcresSquare Feet (ft²)

Distance Unit

Meters (m)Kilometers (km)Miles (mi)Feet (ft)

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Results

What is a Polygon Calculator?

A polygon calculator is a GIS tool that computes geometric properties of polygons including area, perimeter, centroid (center point), and bounding box. This tool supports both manual input (GeoJSON/WKT) and interactive drawing on a map.

Polygon calculations are essential in surveying, land management, urban planning, agriculture, environmental studies, and geographic analysis. Accurate measurements help in property valuation, resource management, and spatial planning.

Key features:

• Area Calculation: Compute polygon area in various units (m², km², acres, hectares)
• Perimeter Calculation: Measure boundary length in meters, kilometers, miles, or feet
• Centroid: Find the geometric center of the polygon
• Interactive Drawing: Draw polygons directly on the map
• Multiple Formats: Support for GeoJSON and WKT input formats

How to Calculate Polygon Area

There are two methods to calculate polygon area:

• Manual Input: Paste GeoJSON or WKT polygon coordinates
• Interactive Drawing: Click on map to draw polygon vertices

The calculator uses geodesic calculations to account for Earth's curvature, providing accurate measurements for large polygons. For smaller areas, the tool automatically adjusts for local coordinate systems.

Area calculation formula depends on the coordinate system. For geographic coordinates (latitude/longitude), the tool uses spherical geometry formulas. For projected coordinates, it uses planar geometry.

Understanding Polygon Perimeter

Perimeter is the total length of the polygon boundary. It's calculated by summing the distances between consecutive vertices along the polygon edge.

For geographic polygons (lat/lon coordinates), the tool uses the Haversine formula to calculate geodesic distances, accounting for Earth's spherical shape. This ensures accuracy for large-scale measurements.

Common Use Cases

Polygon calculations are used in various fields:

• Land Surveying: Measure property boundaries and land parcels
• Agriculture: Calculate field sizes for crop planning and yield estimation
• Urban Planning: Analyze zoning areas and development sites
• Environmental Studies: Measure forest coverage, water bodies, and protected areas
• Real Estate: Calculate property sizes for listings and valuations
• Construction: Estimate material quantities based on area measurements

Area and Perimeter Units

The calculator supports multiple units for flexibility:

Area units:

• Square Meters (m²): Standard metric unit
• Square Kilometers (km²): For large areas like cities or parks
• Hectares (ha): Common in agriculture (1 ha = 10,000 m²)
• Acres: Common in US/UK (1 acre = 4,047 m²)
• Square Miles (mi²): For very large areas

Distance units: meters, kilometers, miles, and feet are available for perimeter measurements.

What is Centroid?

The centroid (also called geometric center or barycenter) is the arithmetic mean position of all points in the polygon. It represents the balance point where the polygon would be perfectly balanced if made of uniform material.

Note: For concave or complex polygons, the centroid might fall outside the polygon boundary. The centroid is different from the center of the bounding box, which is simply the midpoint of the extent.