Cotton strength provided by high volume instruments (HVI) is directly affected by changes in fiber moisture. Additionally, cotton moisture is also affected by changes in humidity of the air when fibers are prepared for strength testing. Experiments were conducted to measure moisture in samples delivered for HVI testing. Instruments using electrical conductivity and near-infrared light absorbance to sense moisture, were compared with weight loss by oven drying. Moisture predictions using a filter-type spectrometer on 50 cottons at six moisture levels, were within 0.17% of oven moisture measured at the same time.