A system is provided for feeding a stream of material. The system includes a feeder, a material density portion, a detector, a weight calculator and an indicator. The feeder can output a portion of the stream of the material from a first position to a second position. The material density portion can generate a density signal based on the density of the material. The detector can detect a volume of the portion of the stream of the material without contacting the portion of the stream of the material and can generate a volume signal based on the detected volume. The weight calculator can calculate a weight based on the density signal and the volume signal and can generate a weight signal. The indicator can provide an indication signal based on the weight signal.