# Drawing Circles with set radius using QGIS

I have a site and want to draw an indicative line in a 5km buffer around the centre of the site. So I want to draw a circle with a radius of 5km. I have a tool for drawing circles and ellipses and rectangles squares and spirals.

None of these let me state the centre point and the radius.

Drop a point (x,y), buffer the point 5km.

i.e. you could make a point in layer and then buffer it into a new layer.

The workflow I have recently been using is to create the point in a Memory Layer, create the buffer into a shapefile saved in a temporary location, then copy and paste the polygon into the final layer. A bit long but works OK.

With mmqgis plugin you can convert your geometry type to centroids :

Plugins > mmqgis > modify > convert geometry type

And then just create buffers on shapes (through Vector > Geoprocessing tools) and precise the desired radius.

You got it

I did something similar - need to draw 5km circles around a set of points meeting some criteria. I solved the problem using styles:

1. Create a Symbology rule for the layer (in my case ": "field" is not null
2. For the symbol, define a 'Simple Marker"

• Size 10000.0 (the size is diameter, not radius
• Units, select "Meters at Scale"
• Fill color: Transparent

Voila! A range ring at true map scale.

I'm using QGis 3.10, which is much newer than when this question was originally asked.

In QGis 3.16 I discovered the'Geometry Shapes' plug-in. The symbol/tool shows up in the digitize toolbar. A very handy plug-in!

• 'Geometry Shapes' plug-in Worked as suggested. You can use it to draw circle or ellipse
– Arti
Feb 22 at 6:21

Possible by means of the `"Rectangles, Ovals, Diamonds"` geoalgorithm from the QGIS's Toolbox, using 'Ovals', either fixed or variable.

Note: That both 'Width' and 'Height' parameters have to be equal.

References:

Consider also using "Geometry Generator" which contains a function `make_circle(\$geometry, 100)`, see image below.

function make_circle
Creates a circular polygon.

Syntax
[ ] marks optional components

Arguments
center center point of the circle
`geom_to_wkt(make_circle(make_point(10,10), 5, 4))``'Polygon ((10 15, 15 10, 10 5, 5 10, 10 15))'`
`geom_to_wkt(make_circle(make_point(10,10,5), 5, 4))``'PolygonZ ((10 15 5, 15 10 5, 10 5 5, 5 10 5, 10 15 5))'`
`geom_to_wkt(make_circle(make_point(10,10,5,30), 5, 4))``'PolygonZM ((10 15 5 30, 15 10 5 30, 10 5 5 30, 5 10 5 30, 10 15 5 30))'`