The amplitude of the ground-state superconducting energy gap Δ(0) and relative jump in the electronic specific heat at the transition temperature ΔC/γT
c are the primary fundamental parameters of any superconductor. Several well-established techniques are available for measuring these values in the bulk samples. However, a limited number of techniques can be used to measure these parameters in atomically thin superconductors. Here, we propose a new approach for extracting Δ(0) and ΔC/γT
c in atomically thin superconductors by utilizing the upper critical field data from perpendicular, Bc2,⊥(T) (when a magnetic field is applied perpendicular to the film surface), and parallel, Bc2,||(T) (when a magnetic field is applied in the direction parallel to the film surface), external field directions. The deduced parameters for few-layer-thick Al, Sn, NbSe2, MoS2, magic angle twisted trilayer graphene (MATTG), and WTe2 are well-matched values expected for strong- and moderately strong-coupled electron-phonon-mediated superconductors. In many reports, the enhancement of Bc2,||(0) above the Pauli-Clogston-Chandrasekhar limiting field (i.e., magnetic field required to break the Cooper pair) in atomically thin superconductors has been explained based on the assumption of exotic pairing mechanisms, for instance, Ising-type pairing. Here, we explain the observed Bc2,||(0) enhancement based on the geometrical enhancement factor that originates from the sample geometry. This approach does not assume the existence of novel exotic pairing mechanisms in atomically thin superconductors.