Island-arc magmatism is a crucial process in the Earth's crustal growth. However, how the island-arc magma production rate (MPR) changes and the key influencing factors remains unclear. This study employs numerical models to simulate island-arc growth, incorporating slab dehydration, mantle hydration and melting, and melt extraction. In addition, the impacts of convergence rate and slab dip angle on island-arc magma production were studied. Results suggest that, (1) MPR increases with higher convergence rates; high convergence rates enhance slab water transport efficiency and mantle wedge convection, thereby promoting water fraction and temperature in potential molten regions; (2) MPR initially rises and then falls as the slab dip angle varies from 30 degrees to 45 degrees, and to 60 degrees. This variation is closely tied to water content in the wedge rather than mantle temperature. However, a higher slab dip promotes dehydration towards the potential-melting mantle wedge, which causes water to ascend to shallow areas and reduces the area of the potential molten region. Ultimately, a dip angle of 45 degrees is optimal for retaining the most suitable water fraction and mantle wedge area, thereby maintaining the largest MPR; (3) convergence rate variation has a much larger influence on magma production rate than dip angle variation. When the convergence rate varies from 2 to 10 cm/a, the largest time-averaged MPR is 64.0 times the smallest one, whereas when the slab dip varies from 30 degrees to 60 degrees, the largest time-averaged MPR is only 3.5 times the smallest one. These findings align with numerous instances observed in modern-day subduction zones.
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