  Anomalous magnetic moment (AMM) of quarks in presence of an external magnetic
field has been explored using a nonlocal Nambu\textemdash Jona-Lasinio (NJL)
model. Various strengths of AMM differing in orders of magnitude are used in
the literature. We explore them in our nonlocal framework to decide on their
strength. We checked the validity of using constant AMM of quarks and
investigate two different temperature and magnetic field dependent forms. The
forms are taken as the AMM being proportional to the i) meanfield and the ii)
square of the meanfield. On comparison with the lattice data for both the
condensate averages and differences, it turns out that the second choice is the
most suitable one, in such an effective model scenario. In the process, we also
keep track of the phase diagram in the $T-eB$ plane arising from our model
calculation. The outcome is reasonable as far as the lattice QCD result is
concerned.
