In this work, a stoichiometric amorphous boron carbide (a-BC) network is constructed via an ab initio molecular dynamics approach. Its structural, electrical and mechanical features are reconnoitered in details and compared with those of turbostratic BC and some important graphite-like amorphous materials. Our computer-generated structure exhibits strong chemical disorder as seen in turbostratic BC. However, it has mixed sp2 and sp3 hybridizations and the average coordination number of B and C atoms is projected to be $$\sim$$ 3.22 and 3.46, correspondingly. Consequently, a-BC appears to be structurally different from turbostratic BC and graphite-like amorphous systems. a-BC is semiconductor having a theoretical band gap of $$\sim$$ 0.20 eV. The bulk, Young’s and shear moduli are estimated as $$\sim$$ 105, 142 and 56 GPa, respectively. Its Vickers hardness is calculated to be about 7–8.5 GPa. a-BC is anticipated to be electronically and mechanically parallel to amorphous boron carbonitride.