Detecting click fraud that includes a processing device that receives data related to a cursor movement towards an advertisement displayed on a web page. The processing device analyzes the cursor movement data and determines a confidence level useable in the determination of click fraud, the confidence level responsive to the analysis of the cursor movement. The received data includes data that the cursor on the web page has transited at least one pixel cluster on the web page prior to a clicking the advertisement. In one embodiment, a click fraud is detected when the click occurred without the cursor crossing a pixel cluster, and no click fraud occurring when the click occurred after the cursor crossed a pixel cluster.