Asymptotic values of the critical exponents &bgr; and &ggr; and amplitudesm0,m0/h0for spontaneous magnetization,M27and initial susceptibility, &khgr;0, are determined by the ‘‘range‐of‐fit’’ scaling‐equation‐of‐state (SES) analysis of the magnetization data, deduced from the ferromagnetic resonance (FMR) spectra taken in the temperature range −0.15≤&egr;=T−TC/TC≤0.15 (TC=Curie temperature) on amorphous (a−) Fe83−XWXB17alloys withX=5 and 9. The exponent values are same as those predicted for three‐dimensional Heisenberg spin system with nearest neighbor interactions. The Gilbert damping parameter &lgr; is temperature‐independent and increases with increasingWconcentration.