Track fatigue signals across study sessions and routines. Improve planning with a single index. Make smarter breaks and sleep choices every study day.
| Date | Study Hours | Sleep Hours | Stress | Break/Hour | Hydration (L) | SFI | Level |
|---|---|---|---|---|---|---|---|
| 2026-02-16 | 5.5 | 7.8 | 4 | 12 | 2.1 | 22 | Low |
| 2026-02-17 | 8.0 | 6.2 | 6 | 8 | 1.4 | 58 | High |
| 2026-02-18 | 6.0 | 7.0 | 7 | 10 | 1.9 | 46 | Moderate |
| 2026-02-19 | 9.0 | 5.8 | 8 | 6 | 1.2 | 79 | Severe |
Use the table as a template for tracking trends. Export your own inputs and results using the download buttons after calculation.
The calculator converts each input into a normalized factor and combines them with weights. The final Study Fatigue Index (SFI) is scaled to a 0–100 range.
SFI = clamp(100 × Raw, 0, 100)
Raw increases with study intensity, sleep deficit, stress, low focus, hydration deficit, caffeine deviation, noise, long streaks, and late sessions. Raw decreases with breaks and movement.
Consistent performance depends on balancing cognitive load and recovery. This calculator converts key daily signals into a 0–100 index so you can compare sessions objectively. A shift from 30 to 55 often reflects a meaningful change in readiness, even when your study hours look similar. Tracking a simple index also reduces guesswork: it turns “I feel tired” into measurable inputs you can adjust.
Study duration, sleep, and stress typically produce the largest swings. For many learners, dropping sleep from 7.5 to 6.0 hours can raise risk sharply, especially on heavy workload days. Break quality matters too: adding 10–15 minutes of rest per hour can offset long sessions by improving attention resets. Focus and noise are included because distractions increase mental effort and error rates.
The bands help you choose the right intensity. Low (0–24) supports deep work and harder topics. Moderate (25–49) is ideal for practice sets, summaries, and revision. High (50–74) suggests shortening blocks, increasing breaks, and choosing lighter tasks like flashcards or organizing notes. Severe (75–100) signals a strong need for recovery before pushing further.
Aim for a repeatable rhythm: 45–60 minutes of work with planned breaks, plus at least 20 minutes of movement daily. Hydration near 2 liters supports alertness, while extreme caffeine patterns can lead to jitteriness or crashes. If you study late, consider shifting complex learning earlier and keeping evenings for review. Also, build a weekly “lighter day” to prevent streak-based overload.
Use the export buttons to save your inputs and results, then compare across dates. Look for patterns such as higher scores after consecutive days, noisy environments, or short sleep. When the index improves while hours stay steady, your routine is becoming more efficient. If the index rises for several days, treat it as an early warning and adjust workload before motivation drops. Pair the index with brief notes on topic difficulty and deadlines, so you can separate true fatigue from challenging material and plan realistic targets with fewer late-night surprises.
No. It is a time-management indicator that summarizes study strain and recovery signals. If you have persistent exhaustion, sleep issues, or health concerns, consult a qualified professional.
Daily works best, ideally after your main session. Consistent timing improves comparability. You can also run it before studying to guide workload selection and break planning.
Many learners should avoid intense tasks above 75. Between 50 and 74, reduce block length and focus on lighter work. Under 50 is typically better for demanding topics.
The model penalizes large deviations from a moderate range because both very low and very high intake can be linked with reduced steadiness, crashes, or disrupted sleep later.
Yes. Keep your inputs consistent and use exports to spot rising fatigue during intensive periods. If streak days and sleep deficit climb together, schedule recovery earlier.
Prioritize sleep, add structured breaks, and include light movement. Reducing noise and stressors can also help quickly. If you are at night sessions, shift key work earlier when possible.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.