Decare and land area calculation app with square metres and measurement method
Decare calculation is simple as a unit conversion, but the measured boundary and method determine whether the result makes sense.
Field takeaways
- 1 decare is 1000 square metres.
- Boundary choice determines the area result.
- Walking measurements are reconnaissance, controlled survey is for professional delivery.
- Horizontal area and surface area should not be confused.
- MapLab Survey connects polygon area, notes and reports.
The units people actually mix up
A decare is 1,000 square metres and a hectare is 10,000. The old Turkish dönüm was roughly 919 square metres, which is why an inherited figure and a modern measurement rarely agree. Before arguing about a discrepancy, check that both numbers use the same unit.
Measure, then convert
Walk or draw the boundary, read the area in square metres and convert once at the end. Converting halfway through a calculation is where rounding errors creep in.
Occupation is not title
What you measure is the current use of the land. The registered area comes from the cadastral record and can differ. Both numbers can be correct at the same time; they answer different questions.
Try these steps on your own phone.
MapLab Survey handles RTK/GNSS point capture, drawing, area and volume calculations and coordinate conversion, then exports to DXF, KML/KMZ, GeoJSON, Shapefile, GeoPackage, NCZ or CSV. Capture, calculation and export work offline. Live NTRIP corrections and online basemaps need a connection.
Frequently asked questions
How many square metres is one decare?
1000 square metres.
How is decare calculated?
Divide square metres by 1000.
Is phone area calculation reliable?
For reconnaissance, not legal survey.
Why can title area and measured area differ?
Boundary and method differences.
Technical references
The field guidance in this article is aligned with the technical and official references below.
Related: Field area calculation · Land square metre calculation · Phone area measurement · MapLab Survey