The liquid junction potential cannot be measured directly but calculated. The electromotive force (EMF) of  a concentration cell with transference includes the liquid junction potential.
The EMF of a concentration cell without transport is:
where  and  are activities of HCl in the two solutions,  is the universal gas constant,  is the temperature and  is the Faraday constant.
The EMF of a concentration cell with transport (including the ion transport number) is:
where  and  are activities of HCl solutions of right and left hand electrodes, respectively, and  is the transport number of Cl.
Liquid junction potential is the difference between the two EMFs of the two concentration cells, with and without ionic transport: