The acquisition of accurate results in use of the electrochemical quartz-crystal nanobalance (EQCN) for surface-electrochemical studies depends on reliability of the value of the calibration constant relating changes of the crystal oscillator frequency to the specific surface mass change resulting from some chemisorption or electrosorption process. Three electrochemical methods are employed comparatively to determine the calibration constant for use of an EQCN. In the, present paper, study of electrodeposition/ electrodissolution of silver on Pt(poly) electrode surfaces provides a means of determining values of the calibration constant for the EQCN response using cyclic voltammetry, chronopotentiometry and chronoamperometry. The experimentally determined value of the calibration constant (C-f) is found to depend on the electrochemical methodology and technique used for its measurement as well as the thickness of the Ag deposit. Use of these three complementary procedures applied, under well-defined conditions provides a basis for adoption of a preferred and reliable procedure for determination of the calibration constant; the resulting mean value is precise and very reproducible. (C) 2003 Elsevier Science Ltd. All rights reserved.