diff --git a/widget/border.go b/widget/border.go
index fac2aa7a..694c9281 100644
--- a/widget/border.go
+++ b/widget/border.go
@@ -21,12 +21,14 @@ type Border struct {
 
 func (b Border) Layout(gtx layout.Context, w layout.Widget) layout.Dimensions {
 	dims := w(gtx)
-	sz := dims.Size
+	sz := layout.FPt(dims.Size)
 
 	rr := float32(gtx.Px(b.CornerRadius))
 	width := float32(gtx.Px(b.Width))
+	sz.X -= width
+	sz.Y -= width
 
-	r := f32.Rectangle{Max: layout.FPt(sz)}
+	r := f32.Rectangle{Max: sz}
 	r = r.Add(f32.Point{X: width * 0.5, Y: width * 0.5})
 
 	paint.FillShape(gtx.Ops,