This study evaluates the silage fermentation quality, rumen fermentation dynamics, degradability, and methane emissions of total mixed rations (TMRs) formulated primarily with varying ratios of pineapple peel and maize husk alongside other agricultural by-products (tofu waste 30%, soy sauce waste 15%, rice bran 10%, and cassava pulp 5%). The TMR formulations differed in crude protein (CP) and neutral detergent fibre (NDF) content due to the changing proportions of pineapple peel (40% to 0%) and maize husk (0% to 40%), with TMR-1, TMR-2, TMR-3, TMR-4, and TMR-5 containing pineapple peel to maize husk ratios of 40:0, 30:10, 20:20, 10:30, and 0:40%, respectively. All TMR silages were well-preserved, as evidenced by low pH (4.06–4.18) and high lactic acid content (1.89–2.25% dry matter). TMR-1 and TMR-2, with lower NDF and higher total digestible nutrients (TDN), demonstrated superior fermentation quality, greater total short-chain fatty acid (TSCFA) production, and lower methane emissions (15.98–15.87% of TSCFA) compared to TMR-4 and TMR-5 (17.85–17.98%). The higher in vitro degradability observed in TMR-1 and TMR- 2 was associated with balanced CP levels (14.02–14.86%) and moderate NDF content (46.06–46.36%), which supported efficient microbial fermentation. In contrast, TMR-4 and TMR-5, with higher NDF content (47.98–48.98%), showed reduced degradability and increased methane production. These results highlight the potential of TMR-1 (40:0) and TMR-2 (30:10) as promising options for beef cattle. However, the lack of vitamin and mineral supplementation is a limitation that should be addressed, and further in vivo studies are necessary to validate nutrient absorption, utilisation, and overall animal performance.