How to Use Fatigue Severity Scale Calculator
- Rate each of the nine FSS statements from 1 to 7 according to the assessment instructions you are following.
- Use the same time frame each time you repeat the scale so results are comparable.
- Calculate to average the nine item scores.
- Read the fatigue severity prompt: lower averages suggest mild fatigue, mid-range values suggest moderate fatigue, and high values suggest severe fatigue.
FSS score = (item 1 + item 2 + ... + item 9) / 9
- Each item uses a 1 to 7 scale, so the final score also ranges from 1 to 7.
- This calculator uses simple bands: 1 to below 4 for mild, 4 to below 6 for moderate, and 6 to 7 for severe.
- The score reflects perceived fatigue impact and should be interpreted with sleep, illness, medication, mood, and workload.
Use Cases for Fatigue Severity Scale Calculator
- Tracking fatigue symptoms across rehabilitation, chronic illness management, or lifestyle changes.
- Preparing concise symptom notes before a healthcare appointment.
- Comparing whether fatigue impact is improving or worsening over time.