An active-energy-ray-curable composition including active-energy-ray-polymerizable compounds, wherein the active-energy-ray-polymerizable compounds include a monofunctional monomer, a bifunctional monomer, and a trifunctional monomer, and wherein the monofunctional monomer, the bifunctional monomer, and the trifunctional monomer satisfy conditions (1) and (2) below: (1) [number of functional groups derived from the monofunctional monomer]>[number of functional groups derived from the bifunctional monomer]>[number of functional groups derived from the trifunctional monomer]; and (2) a standard deviation of functional group ratios is from 0.003 through 0.030, the functional group ratios being expressed by [number of functional groups derived from N-functional monomer]/([number of functional groups derived from the monofunctional monomer]+[number of functional groups derived from the bifunctional monomer]+[number of functional groups derived from the trifunctional monomer]), the N being mono, bi, or tri.