In this paper, the proposed breakdown equation of gases based on energy concept is introduced from initiating stage to complete breakdown (arc) stage. In compounds, the chemical enthalpy represented in bonding energy may be used as a fundamental principle to determine the electrical breakdown voltage. The bond dissociation enthalpy of gaseous compounds indicates the minimum energy needed to release chemical compounds in the material. The breakdown equation based on energy concept is a governing equation and relates between the field of streamer inception E0 and the field in different discharge stages. These stages can be specified from the breakdown index (n) value. Under arc condition, the temperature inside the discharge trail of arc may be up to 19200 K according to the proposed breakdown equation. At this temperature, n equal 64 and the field under arc condition Eb = 8E0. At atmospheric pressure and 1 cm distance electrode gap, the Eb has been calculated for air, N2, H2, and SF6 (36, 39, 18, 81.9 kV/cm respectively). The results comprised in this research compare with experimental and analytical consequences.