In this paper, a method of estimating the quantity of suspended solids in a batch settler is presented. The proposed method is based only on the pressure measurement data that is already available in the settler for measurement of the medium level. It is based on the phenomenon of fractional density changes that can be encountered during sedimentation. Experimental results are presented and it is shown that it is possible to estimate the mass of suspended solids in the batch settler with the measurement error lower than 10%, assuming, that the density of the solid medium is known. (C) 2012 Elsevier B.V. All rights reserved.