<p>The M scale exhibits limitations for earthquakes below magnitude 7.5, as key equations used in its formulation are only applicable for magnitudes up to 7.0. This results in inaccurate energy estimates for smaller and medium events. To overcome this, a unified earthquake catalog has been developed for the Assam region using the recently proposed M_wg scale, which incorporates both short- and long-period seismic data to improve energy estimation. The catalog comprises 8438 events spanning the years 1816–2023. Several region-specific conversion equations were constructed to translate mb, Ms, ML, and MD magnitudes into M_wg, with one particular model demonstrating the highest accuracy. A comparative analysis between M_w- and M_wg-based catalogs reveals significant differences in derived seismic hazard parameters. Declustering of the catalog, using a standard method, removed approximately 22% of the events. The magnitude of completeness improved from 5.7 to 3.7 after 1964, corresponding with the introduction of modern seismological instrumentation. The catalog identifies nine M_wg ≥ 7.0 earthquakes, with none recorded since 1957, indicating a 66-year period of seismic quiescence. This homogenized catalog provides an improved basis for seismicity analysis and supports more reliable probabilistic seismic hazard assessments in this tectonically active region.</p>