Sleep Cycle Disruption Calculator

Estimate your sleep cycle disruption based on sleep duration, timing inconsistency, caffeine intake, and screen time.

Formulas Used

The Sleep Disruption Index is calculated using a weighted formula combining sleep duration, timing inconsistency, caffeine intake, and screen time.

  1. Sleep Duration Score:

    \[ D_{\text{score}} = \max(0, 8 – D) \]

    Where \( D \) is sleep duration in hours, measuring deviation from 8 hours (optimal sleep).

  2. Normalized Caffeine Score:

    \[ C_{\text{norm}} = \min\left(1, \frac{C}{400}\right) \]

    Where \( C \) is caffeine intake in mg, capped at 400 mg for normalization.

  3. Raw Disruption Score:

    \[ R_{\text{raw}} = w_1 D_{\text{score}} + w_2 \left(\frac{T}{2}\right) + w_3 C_{\text{norm}} + w_4 \left(\frac{S}{2}\right) \]

    Where:

    • \( T \): Sleep timing inconsistency in hours (normalized to 2 hours)
    • \( S \): Screen time before bed in hours (normalized to 2 hours)
    • \( w_1 = 10 \): Weight for sleep duration
    • \( w_2 = 15 \): Weight for timing inconsistency
    • \( w_3 = 20 \): Weight for caffeine
    • \( w_4 = 25 \): Weight for screen time

  4. Sleep Disruption Index:

    \[ \text{SDI} = \max\left(0, \min\left(100, \frac{R_{\text{raw}}}{0.95}\right)\right) \]

    Normalizes the raw score to 0–100, with 0.95 as the maximum raw score. Disruption levels: Low (0–25), Moderate (25–50), High (50–75), Severe (75–100).

Example Calculations

Example 1: Typical Night with Moderate Habits

Inputs: Sleep Duration = 6.5 h, Timing Inconsistency = 1 h, Caffeine = 200 mg, Screen Time = 1 h

Calculations:

  • Sleep Duration Score: \[ \max(0, 8 – 6.5) = 1.5 \]
  • Normalized Caffeine: \[ \min\left(1, \frac{200}{400}\right) = 0.5 \]
  • Raw Disruption Score: \[ 10 \cdot 1.5 + 15 \cdot \left(\frac{1}{2}\right) + 20 \cdot 0.5 + 25 \cdot \left(\frac{1}{2}\right) = 15 + 7.5 + 10 + 12.5 = 45 \]
  • Sleep Disruption Index: \[ \frac{45}{0.95} \approx 47.37 \]
  • Disruption Level: Moderate (25–50)

Result: Sleep Disruption Index: 47.4 (Moderate)

Example 2: Poor Sleep with High Caffeine

Inputs: Sleep Duration = 4 h, Timing Inconsistency = 2 h, Caffeine = 400 mg, Screen Time = 2 h

Calculations:

  • Sleep Duration Score: \[ \max(0, 8 – 4) = 4 \]
  • Normalized Caffeine: \[ \min\left(1, \frac{400}{400}\right) = 1 \]
  • Raw Disruption Score: \[ 10 \cdot 4 + 15 \cdot \left(\frac{2}{2}\right) + 20 \cdot 1 + 25 \cdot \left(\frac{2}{2}\right) = 40 + 15 + 20 + 25 = 100 \]
  • Sleep Disruption Index: \[ \frac{100}{0.95} \approx 105.26 \rightarrow 100 \]
  • Disruption Level: Severe (75–100)

Result: Sleep Disruption Index: 100 (Severe)

Example 3: Good Sleep with Minimal Disruption

Inputs: Sleep Duration = 8 h, Timing Inconsistency = 0.5 h, Caffeine = 50 mg, Screen Time = 0.5 h

Calculations:

  • Sleep Duration Score: \[ \max(0, 8 – 8) = 0 \]
  • Normalized Caffeine: \[ \min\left(1, \frac{50}{400}\right) = 0.125 \]
  • Raw Disruption Score: \[ 10 \cdot 0 + 15 \cdot \left(\frac{0.5}{2}\right) + 20 \cdot 0.125 + 25 \cdot \left(\frac{0.5}{2}\right) = 0 + 3.75 + 2.5 + 6.25 = 12.5 \]
  • Sleep Disruption Index: \[ \frac{12.5}{0.95} \approx 13.16 \]
  • Disruption Level: Low (0–25)

Result: Sleep Disruption Index: 13.2 (Low)

How to Use the Calculator

Follow these steps to estimate your sleep cycle disruption:

  1. Enter Sleep Duration: Input average sleep hours per night (0–24, e.g., 7).
  2. Enter Timing Inconsistency: Input variation in bedtime (0–12 hours, e.g., 1 for ±1h).
  3. Enter Caffeine Intake: Input daily caffeine in mg (0–1000, e.g., 200; ~100 mg per coffee).
  4. Enter Screen Time: Input hours of screen use before bed (0–8, e.g., 1).
  5. Calculate: Click “Calculate Sleep Disruption” to see the result.
  6. Interpret Result: The result shows a 0–100 index with a disruption level (Low: 0–25, Moderate: 25–50, High: 50–75, Severe: 75–100). If you see “Please fill in all fields,” ensure all inputs are valid.
  7. Share or Embed: Use the share buttons to post results on social media, copy the result, or get an embed code.

Note: This is a simplified model. Actual sleep disruption depends on additional factors like stress, exercise, and individual differences.