Google Earth Square Footage Calculator: How to Measure

Google Earth does not have a dedicated square footage calculator, but you can use its built-in Ruler tool to measure the area of any polygon and get the result in square feet (or other units). You draw a shape over the area you want, and Google Earth displays the total area, which you can then use for planning, estimating, or comparing with other measurements.

Formula

The calculator above computes the volume of soil, mulch, or other material needed to cover a rectangular area at a given depth. The core formula is:

Volume (cubic feet) = Length (ft) × Width (ft) × Depth (in) ÷ 12

To convert to cubic yards, divide the cubic feet by 27 (since 1 yard = 3 feet, so 1 yd³ = 27 ft³). The calculator combines these steps:

• L = length of the area in feet
• W = width of the area in feet
• D = depth of coverage in inches
• Volume (yd³) = L × W × (D ÷ 12) ÷ 27 = L × W × D ÷ 324

The result in cubic yards is the standard unit for ordering bulk materials like topsoil, compost, or gravel. The cubic feet output is useful for smaller quantities or for comparing with bagged products.

Worked Example

Using the default values from the calculator: a lawn that is 40 feet long, 25 feet wide, and you want to add 3 inches of topsoil.

1. Convert the depth to feet: 3 in ÷ 12 = 0.25 ft
2. Calculate the volume in cubic feet: 40 × 25 × 0.25 = 250 ft³
3. Convert to cubic yards: 250 ÷ 27 = 9.26 yd³

The calculator shows 9.26 yd³ (rounded to two decimals) and 250 ft³. If you order bulk topsoil, you would typically round up to 10 cubic yards to account for settling and spillage.

How the Google Earth Ruler Tool Works

Google Earth’s Ruler tool (available in both the desktop and web versions) lets you measure distances and areas. To get square footage:

1. Open Google Earth on your computer or in a web browser.
2. Navigate to the location you want to measure (use the search box or pan manually).
3. Click the ruler icon in the toolbar (or go to Tools > Ruler in the desktop app).
4. In the Ruler window, choose the “Polygon� tab.
5. Click on the map to place vertices around the perimeter of the area. The shape can be irregular; each click adds a point.
6. Double-click or click the last point to close the polygon.
7. The window will display the area in the units you select. Choose “Square Feet� from the drop-down menu.

The measurement updates as you add points, so you can see the area grow in real time. For a simple rectangle, you could also measure the length and width separately with the “Line� tool and multiply them, but the Polygon tool is more direct.

Why Use Google Earth Instead of a Tape Measure?

Google Earth is ideal for large or inaccessible areas. For example, you can measure the roof area of a house from satellite imagery without climbing a ladder, or estimate the size of a backyard for a new lawn. It is also useful for comparing multiple properties, planning a garden layout, or estimating the area of a field for agricultural purposes.

However, the accuracy depends on the resolution of the satellite images and the precision of your clicks. For most landscaping and property planning, the result is close enough (within a few percent). For legal boundaries or construction, you should always use a professional survey.

Common Mistakes When Measuring in Google Earth

• Using the wrong units – The Ruler tool defaults to meters or miles, so always check the unit dropdown before recording the area.
• Not closing the polygon – If you forget to close the shape, the area may not be calculated or may be incorrect.
• Measuring a sloped surface – Google Earth gives the horizontal (planimetric) area, not the actual surface area of a hill or roof with pitch. For a sloped roof, you would need to account for the slope factor.
• Zoom level – If you are zoomed out too far, it is hard to place points accurately. Zoom in as much as possible for detailed boundaries.
• Mixing up the “Lineâ€� and “Polygonâ€� tabs – The Line tab only gives distance, not area.

Accuracy Limitations and Alternatives

Google Earth’s measurements are based on satellite imagery, which can be offset by a few meters in some regions. For large areas (e.g., a 1-acre lot), the error is usually small relative to the total. But for small, precise measurements (like a garden bed), the error could be significant.

If you need higher accuracy, consider these alternatives:

• Google Maps – Right-click on a map and select “Measure distance,â€� then click to create a shape. It works similarly and is often more up-to-date.
• GIS software – Tools like QGIS (free) or ArcGIS (paid) provide more advanced measurement and analysis.
• GPS devices – A handheld GPS unit can measure area on the ground with higher accuracy for irregular plots.
• Laser distance measurers – For indoor or small outdoor areas, a laser measure plus simple math is quick and precise.

How to Convert the Area to Other Units

Once you have the square footage, you may need to convert it to other units for ordering materials or comparing with listings. Common conversions:

• 1 square foot = 0.0929 square meters
• 1 square meter = 10.764 square feet
• 1 acre = 43,560 square feet
• 1 square yard = 9 square feet

For example, if Google Earth shows an area of 5,000 square feet, that is approximately 464.5 square meters or 0.115 acres. You can use an online converter or do the math manually.

When to Use the Volume Calculator (Not Just Area)

If you are planning to add soil, mulch, or gravel, you need volume, not just area. The calculator at the top of this page helps you determine how many cubic yards to order. Here is a practical example: you measured a garden bed with Google Earth and found it is 20 feet by 10 feet (200 sq ft). You want 2 inches of mulch. Using the formula: 200 × (2/12) = 33.33 cubic feet, which is about 1.23 cubic yards. Most suppliers sell mulch by the cubic yard, so you would order 1.5 or 2 yards (since they often have minimums).

Remember that bulk materials settle, so it is wise to add 5–10% extra. Also, if you are buying bagged mulch (usually 2 cubic feet per bag), you would need 33.33 / 2 = 17 bags (round up to 18).

Frequently Asked Questions

Is Google Earth accurate for measuring square footage?

For most purposes, yes, but accuracy varies by location and image resolution. Typically, measurements are within a few percent of the true ground distance. For critical applications like property lines, use a professional survey.

Can I measure square footage on the Google Earth mobile app?

Yes, the mobile app has a Ruler tool, but it is less precise than the desktop version due to the smaller screen. You can still create polygons and get area measurements, but it may be harder to place points accurately.

Why does Google Earth show area in square meters even when I select feet?

You may have selected “Square Meters� instead of “Square Feet� in the units dropdown. Double-check the unit selection in the Ruler window. Also, the default unit may reset each time you open the tool.

Can I export the measurement from Google Earth?

Yes, you can save the polygon as a KML file and open it in Google Earth Pro or other GIS software to view the area later. In the Ruler window, click “Save� to add the measurement to your Places panel.

Does Google Earth include building heights in area calculations?

No, the area measurement is purely horizontal. If you need the surface area of a sloped roof or a hill, you must adjust for the angle. For a roof, multiply the horizontal area by the pitch factor (e.g., 1.12 for a 4/12 pitch).

What is the maximum area I can measure?

There is no practical limit; you can measure entire countries if you want. However, for very large areas, the curvature of the Earth becomes noticeable, and Google Earth’s flat measurement may differ slightly from true geodetic area. For most property and landscaping uses, this is irrelevant.

Related

• Area of a Circle Calculator in Square Feet
• Area Calculator for Feet and Inches
• Area Calculator UK: Measure Square Metres and Feet

in l | Lawn length | ft | 40 | 0 | 100000
in w | Lawn width | ft | 25 | 0 | 100000
in d | Depth | in | 3 | 0 | 120
out yd | Volume | yd³ | l * w * d / 324 | 2
out ft3 | Volume | ft³ | l * w * d / 12 | 1