The chaos dynamics of a Duffing oscillator. Dimensional analysis is used to reduce the number of dimensionless quantities in the Duffing equation. Phase space plots and Poincarè sections are used to examine the behaviour of the chaotic system. Bifurcation diagrams are also used to describe and quantify the chaos in the system. The Duffing oscillator is found to be a chaotic system that is highly sensitive to initial conditions. The system is also shown to undergo period doubling. Emergence of strange attractors is also evident in the phase space Poincaré section of the system.