Though PERT and CPM both are used for project management,
there are differences between CPM and PERT. The relative table for PERT vs. CPM
is shown below.
PERT uses eventoriented Network.
CPM uses activity oriented
Estimate of time for
activities are not so accurate and definite.
Durations of activity may be
estimated with a fair degree of accuracy.
It is used mostly in research
and development projects, particularly projects of non-repetitive nature.
It is used extensively in
Probabilistic model concept
Deterministic concept is
PERT is basically a tool for
CPM can control both time and
cost when planning.
In PERT, it is assumed that
cost varies directly with time. Attention is therefore given to minimize the
time so that minimum cost results. Thus in PERT, time is the controlling
In CPM, cost optimization is
given prime importance. The time for the completion of the project depends
upon cost optimization. The cost is not directly proportioned to time. Thus,
cost is the controlling factor.