How to Calculate Square Footage Using Google Maps

Remote Measurement September 4, 2026 · 9 min read

Need to know the square footage of a driveway, commercial parking lot, lawn, or rooftop without climbing a ladder or dragging a 100-foot tape measure through wet grass? With modern satellite imagery, you can calculate the square footage or acreage of almost any property directly from your computer.

Google Maps includes a built-in "Measure distance" polygon tool. While it is remarkably accurate for flat ground (driveways, lawns, and concrete pads), calculating a sloped roof requires applying a pitch multiplier to convert the 2D aerial projection into true sloped surface area.

Step-by-Step: Measuring Area on Google Maps

  1. Open Google Maps on your desktop web browser and type in the property address.
  2. Switch to Satellite View (click the layer icon in the lower-left corner) and zoom in directly above the target structure.
  3. Right-click on any corner of the boundary and click "Measure distance".
  4. Click the remaining corners of the property, driveway, or building.
  5. Click back on your original starting point to close the loop.
  6. A pop-up card at the bottom of your screen will instantly display:
    • Total Area: e.g., 2,450 sq ft (227.6 sq m)
    • Total Distance (Perimeter): e.g., 210 ft
Satellite Interface

Google Maps Polygon Measurement

Area: 4,840 ft² (1.0 yd²)

The Roof Pitch Secret: Converting Flat Footprint to Sloped Area

When you measure a roof on Google Maps, you are looking from directly above. A steep roof covers significantly more surface area than its flat aerial footprint.

To calculate true roofing area, multiply your satellite measurement by the slope multiplier:

True Roof Area Formula
True Sloped Area = Satellite Footprint Area × Pitch Multiplier

Live Roof Pitch & Satellite Footprint Tool

Interactive Tool

Roof Pitch & Satellite Multiplier Tool

True Roofing Materials Needed
2,236 sq ft
248.4 Square Yards
Roofing Squares (100 ft²): 23 Squares
With 10% Shingle Waste: 25 Squares (2,460 ft²)

3 Limitations to Keep in Mind

  1. Tree Canopy Obstructions: In heavily wooded neighborhoods, overhanging branches obscure building eaves and lot corners. Use the ruler tool during winter aerial updates when deciduous leaves are off trees.
  2. Eaves & Overhangs: Satellite view measures the roof edge, not the exterior foundation wall. Roof overhangs typically extend 12 to 18 inches beyond walls, making footprints ~5% larger than living space.
  3. Fences vs Legal Boundaries: Fences rarely follow exact property lines. Always cross-reference Google Maps with your county property deed or cadastral plat.

Explore More Mapping & Conversion Tools

Frequently Asked Questions

Right-click the map, select 'Measure distance', click points around the boundary, and click back on your starting point. Google Maps will automatically display Total Area in square feet.

Yes, but satellite photos show the flat 2D footprint. Multiply the flat area by your roof's pitch multiplier (e.g. 1.12x for 6/12 pitch) to find true sloped area.

Google Maps is generally accurate within 2% to 4% for preliminary estimations, asphalt bids, and lawn treatments. It should never be used for legal property disputes.

In roofing, 1 'Square' equals exactly 100 square feet of surface area. A 2,400 sq ft roof requires 24 roofing squares of shingles.

Check your local county property appraiser website, view real estate listings, or measure the exterior footprint directly in Google Maps satellite view.