turf.pointToLineDistance
What is turf.pointToLineDistance?
turf.pointToLineDistance returns the shortest distance from a Point to any segment of a LineString. It walks each segment, computes the perpendicular (or endpoint) distance, and returns the minimum.
turf.pointToLineDistance(point, line, options?) → numberOptions include:
units—'kilometers'(default),'meters','miles','nauticalmiles','radians','degrees'method—'geodesic'(default) or'planar'
When would you use turf.pointToLineDistance?
Use turf.pointToLineDistance for snap-to-line interactions — is this click within N metres of a road? For address-to-street matching in a Node.js pipeline, or for distance-to-coast calculations. It is also handy for filtering a layer to points close to a reference route.
For finding the nearest point on the line itself (not just the distance), pair it with turf.nearestPointOnLine.
undefinedFAQs
What is the difference between geodesic and planar?
geodesic uses spherical/haversine math and is accurate on real Earth coordinates. planar treats longitude/latitude as Cartesian, which is faster but only correct over short distances at moderate latitudes. Stick with geodesic for public-facing mapping.
How do I install just pointToLineDistance?
npm install @turf/point-to-line-distance. Its dependencies include @turf/distance, @turf/helpers, and @turf/invariant.
Does it return the nearest point as well?
No — just the distance. For the projected point on the line, use turf.nearestPointOnLine which returns both the nearest point and its distance.
Does it handle MultiLineString?
Yes — flatten with turf.flatten or iterate, calling pointToLineDistance for each part and taking the minimum. Newer versions of Turf accept LineString Features; check your package version for broader input types.
