Sleep Hygiene Score Calculator
Scores your overall sleep hygiene on a 0–100 scale by rating bedtime consistency, pre-bed screen time, last caffeine intake, and sleep environment. Use it to identify which habits are undermining your sleep.
About this calculator
Sleep hygiene refers to the set of behavioral and environmental practices that support consistent, high-quality sleep. This calculator evaluates four evidence-backed dimensions: bedtime consistency (irregular schedules disrupt the circadian clock), screen exposure before bed (blue light suppresses melatonin), caffeine cutoff timing (caffeine's half-life is ~5 hours, extending alertness long after consumption), and the sleep environment (darkness, quiet, and appropriate temperature). Each dimension is rated on a 1–4 scale, summed, divided by 4 to produce a mean score, then multiplied by 25 to express the result on a 0–100 scale. Formula: Score = ((bedtimeConsistency + screenTime + caffeineTime + environment) ÷ 4) × 25. A score of 75–100 indicates good hygiene; 50–74 suggests room for improvement; below 50 points to habits actively harming sleep quality.
How to use
Suppose your ratings are: bedtimeConsistency = 3 (fairly consistent), screenTime = 2 (screen use within 30 min of bed), caffeineTime = 4 (no caffeine after noon), environment = 3 (mostly dark and quiet). Step 1 — Sum the scores: 3 + 2 + 4 + 3 = 12. Step 2 — Divide by 4: 12 ÷ 4 = 3.0. Step 3 — Multiply by 25: 3.0 × 25 = 75. Your sleep hygiene score is 75/100 — good, but reducing evening screen time could push you into the excellent range.
Frequently asked questions
What does a low sleep hygiene score mean for my health?
A low sleep hygiene score signals that one or more behavioral habits are consistently disrupting your sleep architecture. Poor sleep hygiene is associated with difficulty falling asleep, frequent nighttime awakenings, and reduced time in restorative deep and REM sleep. Over time, chronic poor sleep hygiene contributes to increased risk of anxiety, reduced immune function, impaired cognitive performance, and metabolic disruption. The good news is that sleep hygiene habits are modifiable — even improving one category, such as cutting off caffeine earlier, can produce noticeable gains in sleep quality within days.
How does screen time before bed affect sleep quality and what should I do about it?
Screens emit blue-wavelength light that suppresses melatonin production in the pineal gland, effectively signaling to your brain that it is still daytime. This can delay sleep onset by 30 minutes to over an hour. Beyond light, the cognitive stimulation from social media, news, or video content keeps the brain in an aroused state poorly suited for sleep transition. Experts recommend stopping screen use at least 60 minutes before bed; if screens are unavoidable, using night mode or blue-light-blocking glasses can partially mitigate the melatonin suppression effect.
How long before bed should you have your last caffeine to avoid sleep disruption?
Caffeine has an average half-life of approximately 5–6 hours, meaning half of a 200 mg dose is still active in your bloodstream 5–6 hours after consumption. For most adults, stopping caffeine intake by 2:00 pm allows blood levels to drop sufficiently before a 10:00 pm bedtime. However, genetic variation in the CYP1A2 enzyme means slow metabolizers may feel caffeine's effects for up to 10–12 hours. If you struggle to fall asleep despite seemingly cutting off caffeine early, consider moving your last cup to before noon as a trial.