# QGIS Measure Distance Using Field Calculator

I have a point shapefile with 80K+ records. Shapefile is projected in wgs84. The shapefile contains fields with the latitude and longitude of the point. I need a new field that contains a distance from a known point (Point B) in each record. Point B is the same for every record in the shapefile. There is a distance function in the field calculator (field calculator -> geometry -> distance). But I can't make sense of the syntax.

Example:

``````distance( geom_from_wkt( 'POINT(4 4)' ), geom_from_wkt( 'POINT(4 8)' ) ) → 4
``````

What I want to do is measure the distance from the geometry of the current point to the geometry of a point I supply (for example point at "25.906543, -80.546800"). How do I refer to the current record using that tool and how to a create the new geometry? Is is something like:

``````distance( geom_from_wkt( 'POINT(25.906543, -80.546800)' ),
(\$geometry ) )
``````
• Have you had a look at the tool `distance matrix`? If so, how does it not suit your needs? Also, distance calculations using the field calculator in QGIS are done in the CRS of the layer, so based on a WGS84 layer you'd get distance in degree. – Erik Sep 11 '19 at 13:29
• Disclaimer: I have experience with ESRI software, so I my comments might use ESRI-specific terminology. Distance matrix might work. If I understand it correctly, it will create a new table with fields for the unique id of the "from" table and one with the calculated distance. I could then join those tables on the unique ID and then calculate the distance into a new field in the "from" table. – bdwyer Sep 11 '19 at 17:21
• Thanks for the response. I went with babel's solution because it added a field with the distance. I didn't have to create another table. – bdwyer Sep 11 '19 at 19:15

``````length(make_line(make_point(25.906543, -80.546800),\$geometry))
you create a line (`make_line`), starting at the point with your fixed coordinates (created with the command `make_point(25.906543, -80.546800)`) and ending at the second point, defined with `\$geometry` as the current point of your layer. You then measure the length with the expression `length()` If you create a new field with the field-calculator, you get a new field containing the distances for each point of your layer to the point at 25.906543, -80.546800