Disclosed are approaches for determining a processing endpoint using individually measured target spectra. More specifically, one approach includes: measuring a white light (WL) target spectra of a semiconductor device on an individual wafer prior to formation of a polishing/planarization material; inputting the WL target spectra to a WL endpoint algorithm of the semiconductor device following formation of the polishing/planarization material; and determining, using the WL endpoint algorithm, the processing endpoint of the polishing/planarization material of the semiconductor device. In another approach, the endpoint measurement process comprises receiving spectra reflected from the semiconductor device during polishing, and comparing the spectra to the WL target spectra, which is previously stored within a storage device. As such, WL target spectra are measured “as is” (e.g., without simplifications, generalizations, assumptions, etc.) for each wafer to reduce complications inherent with the use of an uncertain and/or estimated target.