Atomic force microscopy (AFM) friction measurements on hard and soft materials remain a challenge due to the difficulties associated with accurately calibrating the cantilever for lateral force measurement. One of the most widely accepted lateral force calibration methods is the wedge method. This method is often used in a simplified format but in so doing sacrifices accuracy. In the present work, we have further developed the wedge method to provide a lateral force calibration method for integrated AFM probes that is easy to use without compromising accuracy and reliability. Raw friction calibration data are collected from a single scan image by continuous ramping of the set point as the facets of a standard grating are scanned. These data are analysed to yield an accurate lateral force conversion/calibration factor that is not influenced by adhesion forces or load deviation. By demonstrating this new calibration method, we illustrate its reliability, speed and ease of execution. This method makes accessible reliable boundary lubrication studies on adhesive and heterogeneous surfaces that require spatial resolution of frictional forces. •We develop a simple and accurate method for lateral force calibration in AFM friction measurements.•We detail the basis of the method and illustrate how to use it and its reliability with example data.•Our method is easy, accurate and accounts for the affects of adhesion on friction measurements.•The method is applicable to integrated probes, as opposed to colloidal probes.•This allows accurate AFM friction measurements on spatially heterogeneous and adhesive surfaces.