Guides to measuring land
Clear, practical explanations — how to measure, how accurate it is, and how to read and convert the numbers — with worked examples you can check in our free tools.
How to Measure Land Area with Your Phone
Tap corners on a satellite map, walk the boundary with GPS, type in surveyed coordinates, or trace by hand. Here is when each method works best and how to sanity-check the number you get.
Read the guideHow to Calculate the Acreage of an Irregular Lot
Split the lot into triangles, use the trapezoid or offsets method, or compute straight from corner coordinates. Worked examples show each method and why averaging opposite sides overestimates.
Read the guideHow Many Square Feet Are in an Acre?
An acre is 43,560 square feet, the area of a strip one chain wide and one furlong long. Here is what that looks like, how it converts to metric, and a table of common lot sizes.
Read the guideHow Accurate Is Phone GPS for Measuring Land?
Phone GPS is typically good to a few meters under open sky. Learn what the accuracy figure means, why small plots are hit hardest, when averaging helps, and how to get the best result.
Read the guideHow to Measure a Field's Perimeter for Fencing
Get the perimeter from a map, a GPS walk, or a tape, then turn it into posts, wire, and a cost estimate. Includes the post-count rule, gates and bracing, and a worked two-acre paddock.
Read the guideDMS vs Decimal Degrees: How to Read and Convert GPS Coordinates
The three common ways to write latitude and longitude, how to convert between them by hand, and the small mistakes that put a point kilometers away.
Read the guideKML vs GPX vs GeoJSON (and CSV): Which File Format for Land Boundaries?
A practical comparison of the common geographic file formats, with the same small square written in each, so you can pick the right one for a boundary, a walked track, or a spreadsheet.
Read the guideTraditional Land Units Around the World: Bigha, Rai, Tsubo, Feddan and More
Where traditional land units are still used, which ones have a single fixed size, and which ones change from place to place, so you know when a conversion needs a local check.
Read the guideHow to Walk a Property Boundary with GPS and Get a Useful Measurement
Walking a boundary with a phone can give a good working estimate of a property's size and perimeter, if you prepare, take care at the corners, and know the common errors.
Read the guideHow to Calculate Area from GPS Coordinates (With Worked Examples)
The math behind turning a list of latitude and longitude points into an area and a perimeter: local projection with the shoelace formula, spherical polygon area, and how they compare.
Read the guide