Blog · September 27, 2026
Chord and Radius on a Plat
The radius is the distance from the curve's center to the arc. The chord is the straight line between the arc's endpoints.
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Plats print both so a surveyor can stake the curve. The radius sets how sharp the turn is. The chord bearing helps check the drawing.
On the recorded sheet
A long radius is a flat curve. A short radius is a tight corner. The lot line follows whichever the plat calls the boundary.
The mix-up to avoid
Scaling a radius off a PDF enlarges the error. Use the printed number.
Find the county map
Search the county on the Platbookmapper home page. The directory links to the official parcel viewer. It does not draw the lots, and the line on the screen is an assessment map, not a survey.
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey.