Measuring Distances and Areas
Google Earth offers a number of tools that you can use to measure distances and estimate sizes. Depending upon which version of Google Earth you are using, you have access to the following measuring tools:
- Measuring with a line or path (all Google Earth versions)
- Measuring with a circle radius or polygon (Google Earth PRO)
Use the 'Ruler' window ('Tools' menu) or click 
to measure length, area, and circumference as follows:
- Position the imagery you want to measure within the 3D viewer and make sure you are viewing the earth from top-down (type U) and with terrain turned off for best accuracy. Measuring is calculated using the lat/lon coordinates from point to point and does not consider elevation.
- From the Tools menu, select Ruler. The Ruler dialog box appears. Consider moving the dialog box to a region of your screen that doesn't obstruct the 3D viewer.
- Choose the type of shape you want to measure with. All versions of Google Earth can measure with Line or Path. Google Earth PRO users can also measure using a polygon or circle.
- Choose the unit of measure for length, perimeter, area, radius, or circumference, as applicable. See the table below for a list of supported units of measure.
- Click in the 3D viewer to set the beginning point for your shape and continue clicking until the line, path, or shape measures the desired region. (For circle, click in the center and drag out to define the circle.)
A red dot indicates the beginning point of your shape, and a yellow line connects to it as you move the mouse. Each additional click adds a new line to the shape, depending upon the tool you chose. The total units for the shape are defined in the Ruler dialog box, and you can choose other units of measure for the existing shape.
For more details on how to modify the shape, reposition the viewer while measuring, and use other shape features, see the features table.
