Conventional GPC setup employs a concentration detector (Refractive Index or UV/VIS) to obtain the relative molecular weights and distribution of polymers. This technique requires column calibration using known narrow molecular weight distribution standards. In order to obtain accurate molecular weight values, the standards have to be of the same or similar structure as that of the sample. Depending on the sample distribution, typically 8 to 12 standards can generate a reasonable calibration curve.

Conventional GPC is the most accurate method for determination of molecular weight distribution (Polydispersity) and is widely used for routine quality control of known products. Conventional GPC is also most useful when comparing supposedly identical products. For instance, in the polymer processing industry slight variation in distribution can separate “in-spec” from “off-spec” batches of samples having the same technical specifications.