We present a first-principles derivation of the Higgs boson mass, electroweak coupling constants, strong coupling constant, and Newtonian gravitational constant, based on our fundamental particle spin model. We demonstrate that the spin angular momenta of fundamental particles arise from the circular motion of their fundamental charges (FCs). The reduced energy generated by the interactions of the FCs in a fundamental particle spread out as wave with wavelength equivalent to the speed of light divided by the frequency of the circular motion. While the motion of the FCs in a fundamental particle that generates the spin angular momentum is circular, the corresponding wave propagation is linear. For the linear distance of this wave to equal the diameter of the interaction sphere, the system's energy must be multiplied by π. In the case of the weak interaction, this energy corresponds to the sum of the rest energies of the W+, W-, and Z0 bosons that mediate the interaction, the vacuum expectation value, or twice the rest energy of a Higgs boson. This provides a theoretical foundation for the non-zero vacuum expectation value of the Higgs field and yields equations for the electroweak coupling constants and the Higgs boson mass, allowing their derivation without relying on experimental data. For the strong interaction, the system's energy is π times the energy of a quark within a charged pion. Based on this energy, we determine the strong coupling constant at zero momentum transfer, quantitatively explaining the large difference in strength between the electromagnetic and strong interactions. For gravity, we derive the gravitational constant from the relative magnitudes of fundamental particle masses. The resulting theoretical coupling constants exhibit strong agreement with experimental values, and our accurate prediction of a Higgs boson mass of 125.5 GeV/c² further validates the model.