Measure land from a survey or plat image

When this tool is useful

If you already have a survey, plat, subdivision sketch, site plan or scanned property drawing with at least one known dimension, you may not need a satellite map to estimate area. The known line provides a scale. Once calibrated, the traced polygon can be converted from image pixels into real-world dimensions.

Why one known dimension matters

An image by itself has pixels, not feet or metres. The calibration line tells the tool how many real-world feet correspond to each pixel. Area then scales by the square of that ratio, so a poorly chosen or inaccurately clicked scale line can materially affect the result.

Choose the longest reliable dimension you can

For better precision, use a clearly labelled line that is relatively long on the image. A 200-foot property side generally gives a more stable scale than a tiny 8-foot annotation because a one-pixel clicking error represents a smaller percentage of the reference length.

Scanned documents can be distorted

If a paper survey was photographed at an angle, stretched, skewed or scanned non-uniformly, one scale may not be equally accurate across the whole image. Use this tool for planning and cross-checking, not to establish a legal property boundary.

What this estimate does — and does not — tell you

The result can help answer questions like “approximately how many acres are shown on this plat?” or “what is the approximate perimeter for a fence estimate?” It does not replace deed calls, bearings, monuments, easements, parcel records or a licensed boundary survey.

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