About Satellite Area Calculator
A free web tool for measuring area and distance on satellite imagery, built by an independent developer. No accounts, no data collection, no fees.
What this tool does
Satellite Area Calculator lets you draw polygons and circles directly on a satellite map and see the enclosed area, perimeter, and radius in real time. Measurements use Google Maps' spherical geometry library, which accounts for Earth's curvature — so a 50-acre field at the equator and a 50-acre field in Alaska both compute correctly.
The tool supports five area units (m², ft², acres, hectares, square miles), four distance units (m, ft, km, miles), and unlimited shapes per session. There's also a natural-language assistant that can draw shapes for you — useful when you know the location by name but don't want to scroll the map there.
Who it's for
The tool was originally built for personal property planning. Over time, it picked up users from a wider set of fields:
- Homeowners estimating lot sizes, fence runs, or garden plots
- Solar installers sizing rooftop systems before a site visit
- Farmers measuring fields, paddocks, and irrigation areas
- Real estate agents preparing listings
- Surveyors and planners doing rough preliminary estimates
- Researchers and students working with geographic data
- Anyone curious how big something looks from above
What it isn't
This isn't a substitute for a professional survey. The accuracy of any measurement is bounded by the resolution of the underlying satellite imagery and the precision with which you click the corners. For legal property boundaries, easements, building permits, or anything that ends up in court — hire a licensed surveyor.
Read more about the limits of consumer satellite imagery in our accuracy guide.
Who built it
The tool was built by James Patton, an independent web developer working on practical, no-friction tools. If you'd like to get in touch about a bug, a feature request, or a collaboration, the contact page has a LinkedIn link.
Tech stack, briefly
The frontend is Vue 3 with Vite. The drawing layer uses Terra Draw on top of Google Maps. Area calculations call into Google's spherical geometry library. There's a small Express backend that brokers natural-language commands through OpenAI for the chat assistant.