turf.convex
What is turf.convex?
turf.convex returns the tightest convex polygon containing all coordinates of the input features. It accepts any GeoJSON input — FeatureCollection, Polygon, LineString, Point — and returns a single Polygon Feature.
turf.convex(geojson, options?) → Feature<Polygon>Options include:
concavity— value between 1 and Infinity; controls concavity.Infinityis fully convex (default), smaller values approach concave. Available in some versions via@turf/concaveman.properties— output feature properties
When would you use turf.convex?
Use turf.convex when you need a simple, always-valid polygon summarising a set of features — for example, bounding customer locations for a coverage analysis, delimiting a search area around a set of POIs, or computing a basic service zone.
Convex hulls are computationally cheap and topologically safe (no self-intersection). They are the right choice when a loose envelope is acceptable; for shape-conforming outlines use turf.concave.
undefinedFAQs
When should I use concave instead?
When the point set has noticeable clusters or gaps that the convex hull smooths over. turf.concave follows indentations and produces more realistic outlines for sparse, clustered data — at the cost of tuning maxEdge.
How do I install just convex?
npm install @turf/convex. It depends on @turf/helpers and @turf/meta; recent versions integrate with concaveman internally.
What if I have just two points?
turf.convex needs at least 3 non-collinear points to form a polygon. With fewer, it returns null or throws, depending on the version — handle the degenerate case in your wrapper code.
Does it preserve input properties?
No — the hull is a new polygon with the properties you pass in options (or empty by default). Input properties are not carried through because the hull can span many input features.
