Factors affecting the subjective loudness of tinnitus were analyzed using quantitative methods. One hundred and eighty-four patients with unilateral tinnitus were studied. Major factors affecting the subjective loudness of tinnitus were found to be subjective tinnitus pitch, annoyance, diagnosis, pitch-matched frequency, insomnia, age, tinnitus loudness level in dB HL, the duration of tinnitus and the tinnitus loudness level in dB SL at the first axis. Tinnitus pitch and pitch-matched frequency strongly affected the loudness of the tinnitus; high-pitch tinnitus and middle and low frequencies were associated with the subjective loudness of the tinnitus. In contrast, low-pitch tinnitus and a high frequency were associated with the subjective softness of the tinnitus. Thus, tinnitus pitch and pitch-matched frequency are inversely related. Sudden deafness and dizziness were associated with subjective softness of tinnitus, while hearing loss in elderly patients was associated with subjective loudness of tinnitus. Our results suggest that the level of annoyance from tinnitus and the subjective loudness of tinnitus are closely related. The relation between these factors should be considered when evaluating patients with tinnitus.