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Size at metamorphosis may influence terrestrial performance of anurans in numerous ways. I examined the diet of recently metamorphosed spadefoot toads (Scaphiopus couchii) of varying size to see if body size influenced foraging success. Prey availability was examined using sticky traps. Toadlets ate a wide size range (0.2 to >15 mm in length) of arthropod prey. In moist habitats where toadlets were active, small arthropods were abundant and toadlets of all sizes had numerous prey items in their stomachs. Prey sizes and taxa varied with toadlet size; smaller toadlets ate prey of smaller minimum, mean, and maximum sizes than larger toadlets. Smaller prey were relatively more abundant on sticky traps, suggesting that the prey size distribution of the smallest toadlets most closely matched the size distribution of prey available. Larger toadlets were more selective in their prey choice. In feeding trials, larger toadlets were much better than small toadlets at capturing prey (pinhend crickets) that were at the higher end of the prey size distribution of the smaller toadlets. However, at least on moist soil, arthropods of all sizes were available, and the body size of field-collected toadlets was unrelated to the number of prey items in the stomach. Larger toadlets may only have a foraging advantage under crowded conditions, or as soil dries and size-dependent biophysical constraints on activity are imposed.